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Population count

From Rosetta Code


Task
Population count
You are encouraged to solve this task according to the task description, using any language you may know.

The   population count   is the number of   1s   (ones)   in the binary representation of a non-negative integer.

Population count   is also known as:

  •   pop count
  •   popcount
  •   sideways sum
  •   bit summation
  •   Hamming weight


For example,   5   (which is   101   in binary)   has a population count of   2.


Evil numbers   are non-negative integers that have an   even   population count.

Odious numbers     are  positive integers that have an    odd   population count.


Task
  • write a function (or routine) to return the population count of a non-negative integer.
  • all computation of the lists below should start with   0   (zero indexed).
  • display the   pop count   of the   1st   thirty powers of   3       (30,   31,   32,   33,   34,   ∙∙∙   329).
  • display the   1st   thirty     evil     numbers.
  • display the   1st   thirty   odious   numbers.
  • display each list of integers on one line   (which may or may not include a title),   each set of integers being shown should be properly identified.


See also



360 Assembly[edit]

Use of the old " Unnormalized Double Floating Point" feature, a bit forgotten, to have 56-bit integers. And also use of ICM (Insert Characters Under Mask) and TM (Test under Mask) to handle bits.
Let's note:

  • in Normalized Double Floating Point, one is implemented X'4110000000000000'
  • in Unnormalized Double Floating Point, one is implemented X'4E00000000000001'


*        Population count          09/05/2019
POPCNT CSECT
USING POPCNT,R13 base register
B 72(R15) skip savearea
DC 17F'0' savearea
SAVE (14,12) save previous context
ST R13,4(R15) link backward
ST R15,8(R13) link forward
LR R13,R15 set addressability
LD F0,UN 1
STD F0,BB bb=1
MVC PG(7),=C'pow 3:' init buffer
L R10,NN nn
BCTR R10,0 nn-1
LA R9,PG+7 @pg
LA R6,0 i=0
DO WHILE=(CR,R6,LE,R10) do i=0 to nn-1
LM R0,R1,BB r0r1=bb
BAL R14,POPCOUNT call popcount(bb)
LR R1,R0 popcount(bb)
XDECO R1,XDEC edit popcount(bb)
MVC 0(3,R9),XDEC+9 output popcount(bb)
LD F0,BB bb
AW F0,BB bb*2
AW F0,BB bb*3
STD F0,BB bb=bb*3
LA R9,3(R9) @pg
LA R6,1(R6) i++
ENDDO , enddo i
XPRNT PG,L'PG print buffer
SR R7,R7 j=0
DO WHILE=(C,R7,LE,=F'1') do j=0 to 1
MVC PG,=CL132' ' clear buffer
IF LTR,R7,Z,R7 THEN if j=0 then
MVC PG(7),=C'evil: ' init buffer
ELSE , else
MVC PG(7),=C'odious:' init buffer
ENDIF , endif
LA R9,PG+7 @pg
SR R8,R8 n=0
SR R6,R6 i=0
DO WHILE=(C,R8,LT,NN) do i=0 by 1 while(n<nn)
XR R0,R0 r0=0
LR R1,R6 r1=i
BAL R14,POPCOUNT r0=popcount(i)
SRDA R0,32 ~
D R0,=F'2' popcount(i)/2
IF CR,R0,EQ,R7 THEN if popcount(i)//2=j then
LA R8,1(R8) n=n+1
XDECO R6,XDEC edit i
MVC 0(3,R9),XDEC+9 output i
LA R9,3(R9) @pg
ENDIF , endif
LA R6,1(R6) i++
ENDDO , enddo i
XPRNT PG,L'PG print buffer
LA R7,1(R7) j++
ENDDO , enddo j
L R13,4(0,R13) restore previous savearea pointer
RETURN (14,12),RC=0 restore registers from calling sav
*------- ---- ------------------
POPCOUNT EQU * popcount(x)
ICM R0,B'1000',=X'00' zap exponant part
XR R3,R3 y=0
LA R4,56 mantissa size = 56
LOOP STC R1,CC do i=1 to 56
TM CC,X'01' if bit(x,i)=1
BNO NOTONE then{
LA R3,1(R3) y++}
NOTONE SRDA R0,1 shift right double arithmetic
BCT R4,LOOP enddo i
LR R0,R3 return(y)
BR R14 return
*------- ---- ------------------
NN DC F'30' nn=30
BB DS D bb
UN DC X'4E00000000000001' un=1 (unnormalized)
PG DC CL132' ' buffer
XDEC DS CL12 temp for xdeco
CC DS C
REGEQU
END POPCNT
Output:
pow  3:  1  2  2  4  3  6  6  5  6  8  9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
evil:    0  3  5  6  9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
odious:  1  2  4  7  8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

Ada[edit]

Specification and implementation of an auxiliary package "Population_Count". The same package is used for Pernicious numbers#Ada

with Interfaces;
 
package Population_Count is
subtype Num is Interfaces.Unsigned_64;
function Pop_Count(N: Num) return Natural;
end Population_Count;
package body Population_Count is
 
function Pop_Count(N: Num) return Natural is
use Interfaces;
K5555: constant Unsigned_64 := 16#5555555555555555#;
K3333: constant Unsigned_64 := 16#3333333333333333#;
K0f0f: constant Unsigned_64 := 16#0f0f0f0f0f0f0f0f#;
K0101: constant Unsigned_64 := 16#0101010101010101#;
X: Unsigned_64 := N;
begin
X := X - (Shift_Right(X, 1) and k5555);
X := (X and k3333) + (Shift_Right(X, 2) and k3333);
X := (X + (Shift_Right(X, 4)) and K0f0f);
X := Shift_Right((x * k0101), 56);
return Natural(X);
end Pop_Count;
 
end Population_Count;

The main program:

with Ada.Text_IO, Population_Count; use Ada.Text_IO; use Population_Count;
 
procedure Test_Pop_Count is
 
X: Num; use type Num;
 
begin
Put("Pop_Cnt(3**i):"); -- print pop_counts of powers of three
X := 1; -- X=3**0
for I in 1 .. 30 loop
Put(Natural'Image(Pop_Count(X)));
X := X * 3;
end loop;
New_Line;
 
Put("Evil: "); -- print first thirty evil numbers
X := 0;
for I in 1 .. 30 loop
while Pop_Count(X) mod 2 /= 0 loop -- X is not evil
X := X + 1;
end loop;
Put(Num'Image(X));
X := X + 1;
end loop;
New_Line;
 
Put("Odious: "); -- print thirty oudous numbers
X := 1;
for I in 1 .. 30 loop
while Pop_Count(X) mod 2 /= 1 loop -- X is not odious
X := X + 1;
end loop;
Put(Num'Image(X));
X := X + 1;
end loop;
New_Line;
end Test_Pop_Count;
Output:
Pop_Cnt(3**i): 1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
Evil:          0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
Odious:        1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

ALGOL 68[edit]

# returns the population count (number of bits on) of the non-negative       #
# integer n #
PROC population count = ( LONG INT n )INT:
BEGIN
LONG INT number := n;
INT result := 0;
WHILE number > 0 DO
IF ODD number THEN result +:= 1 FI;
number OVERAB 2
OD;
result
END # population # ;
 
# population count of 3^0, 3^1, 3*2, ..., 3^29 #
LONG INT power of three := 1;
print( ( "3^x pop counts:" ) );
FOR power FROM 0 TO 29 DO
print( ( " ", whole( population count( power of three ), 0 ) ) );
power of three *:= 3
OD;
print( ( newline ) );
# print the first thirty evil numbers (even population count) #
INT evil count := 0;
print( ( "evil numbers  :" ) );
FOR n FROM 0 WHILE evil count < 30 DO
IF NOT ODD population count( n ) THEN
print( ( " ", whole( n, 0 ) ) );
evil count +:= 1
FI
OD;
print( ( newline ) );
# print the first thirty odious numbers (odd population count) #
INT odious count := 0;
print( ( "odious numbers:" ) );
FOR n WHILE odious count < 30 DO
IF ODD population count( n ) THEN
print( ( " ", whole( n, 0 ) ) );
odious count +:= 1
FI
OD;
print( ( newline ) )
 
Output:
3^x pop counts: 1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
evil numbers  : 0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
odious numbers: 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

ALGOL W[edit]

begin
 % returns the population count (number of bits on) of the non-negative integer n %
integer procedure populationCount( integer value n ) ;
begin
integer v, count;
v  := n;
count := 0;
while v > 0 do begin
if odd( v ) then count := count + 1;
v  := v div 2
end while_v_gt_0 ;
count
end populationCount ;
 % returns the sum of population counts of the elements of the array n  %
 % the bounds of n must be 1 :: length  %
integer procedure arrayPopulationCount( integer array n ( * ); integer value length ) ;
begin
integer count;
count := 0;
for i := 1 until length do count := count + populationCount( n( i ) );
count
end arrayPopulationCount ;
begin %task requirements %
integer array power( 1 :: 8 );
integer n, count, carry;
 % population counts of the first 30 powers of three %
 % Algol W integers are 32-bit, so we simulate 64-bit with an array of integers %
 % the only operation we need is multiplication by 3  %
 % we use 8 bits of each number  %
 % start with 3^0, which is 1 %
for i := 1 until 8 do power( i ) := 0;
power( 1 ) := 1;
write( i_w := 1, s_w := 0, "3^x population: ", arrayPopulationCount( power, 8 ) );
for p := 1 until 29 do begin
carry := 0;
for b := 1 until 8 do begin
integer bValue;
bValue  := ( power( b ) * 3 ) + carry;
carry  := bValue div 256;
power( b ) := bValue rem 256
end for_b ;
writeon( i_w := 1, s_w := 0, " ", arrayPopulationCount( power, 8 ) )
end for_p ;
 
 % evil numbers (even population count) %
write( "evil numbers:" );
n  := 0;
count := 0;
while count < 30 do begin
if not odd( populationCount( n ) ) then begin
writeon( i_w := 1, s_w := 0, " ", n );
count := count + 1
end if_not_odd_populationCount ;
n := n + 1
end evil_numbers_loop ;
 
 % odious numbers (odd population count %
write( "odious numbers:" );
n  := 0;
count := 0;
while count < 30 do begin
if odd( populationCount( n ) ) then begin
writeon( i_w := 1, s_w := 0, " ", n );
count := count + 1
end if_odd_populationCount ;
n := n + 1
end odious_numbers_loop
end
end.
Output:
3^x  population: 1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
evil    numbers: 0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
odious  numbers: 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

AppleScript[edit]

Translation of: JavaScript
--------------------- POPULATION COUNT ---------------------
 
-- populationCount :: Int -> Int
on populationCount(n)
-- The number of non-zero bits in the binary
-- representation of the integer n.
 
script go
on |λ|(x)
if 0 < x then
Just({x mod 2, x div 2})
else
Nothing()
end if
end |λ|
end script
 
integerSum(unfoldr(go, n))
end populationCount
 
 
--------------------------- TEST ---------------------------
on run
set {evens, odds} to partition(compose(even, populationCount), ¬
enumFromTo(0, 59))
 
unlines({"Population counts of the first 30 powers of three:", ¬
tab & showList(map(compose(populationCount, raise(3)), ¬
enumFromTo(0, 29))), ¬
"", ¬
"First thirty 'evil' numbers:", ¬
tab & showList(evens), ¬
"", ¬
"First thirty 'odious' numbers:", ¬
tab & showList(odds)})
end run
 
 
------------------------- GENERIC --------------------------
 
-- Just :: a -> Maybe a
on Just(x)
-- Constructor for an inhabited Maybe (option type) value.
-- Wrapper containing the result of a computation.
{type:"Maybe", Nothing:false, Just:x}
end Just
 
 
-- Nothing :: Maybe a
on Nothing()
-- Constructor for an empty Maybe (option type) value.
-- Empty wrapper returned where a computation is not possible.
{type:"Maybe", Nothing:true}
end Nothing
 
 
-- compose (<<<) :: (b -> c) -> (a -> b) -> a -> c
on compose(f, g)
script
property mf : mReturn(f)
property mg : mReturn(g)
on |λ|(x)
mf's |λ|(mg's |λ|(x))
end |λ|
end script
end compose
 
 
-- enumFromTo :: Int -> Int -> [Int]
on enumFromTo(m, n)
if m ≤ n then
set lst to {}
repeat with i from m to n
set end of lst to i
end repeat
lst
else
{}
end if
end enumFromTo
 
 
-- even :: Int -> Bool
on even(x)
0 = x mod 2
end even
 
 
-- foldl :: (a -> b -> a) -> a -> [b] -> a
on foldl(f, startValue, xs)
tell mReturn(f)
set v to startValue
set lng to length of xs
repeat with i from 1 to lng
set v to |λ|(v, item i of xs, i, xs)
end repeat
return v
end tell
end foldl
 
 
-- map :: (a -> b) -> [a] -> [b]
on map(f, xs)
-- The list obtained by applying f
-- to each element of xs.
tell mReturn(f)
set lng to length of xs
set lst to {}
repeat with i from 1 to lng
set end of lst to |λ|(item i of xs, i, xs)
end repeat
return lst
end tell
end map
 
 
-- mReturn :: First-class m => (a -> b) -> m (a -> b)
on mReturn(f)
-- 2nd class handler function lifted into 1st class script wrapper.
if script is class of f then
f
else
script
property |λ| : f
end script
end if
end mReturn
 
-- partition :: (a -> Bool) -> [a] -> ([a], [a])
on partition(f, xs)
tell mReturn(f)
set ys to {}
set zs to {}
repeat with x in xs
set v to contents of x
if |λ|(v) then
set end of ys to v
else
set end of zs to v
end if
end repeat
end tell
{ys, zs}
end partition
 
-- raise :: Num -> Int -> Num
on raise(m)
script
on |λ|(n)
m ^ n
end |λ|
end script
end raise
 
 
-- integerSum :: [Num] -> Num
on integerSum(xs)
script addInt
on |λ|(a, b)
a + (b as integer)
end |λ|
end script
 
foldl(addInt, 0, xs)
end integerSum
 
 
-- intercalate :: String -> [String] -> String
on intercalate(delim, xs)
set {dlm, my text item delimiters} to ¬
{my text item delimiters, delim}
set s to xs as text
set my text item delimiters to dlm
s
end intercalate
 
 
-- showList :: [a] -> String
on showList(xs)
"[" & intercalate(",", map(my str, xs)) & "]"
end showList
 
 
-- str :: a -> String
on str(x)
x as string
end str
 
 
-- unfoldr :: (b -> Maybe (a, b)) -> b -> [a]
on unfoldr(f, v)
-- A list derived from a simple value.
-- Dual to foldr.
-- unfoldr (\b -> if b == 0 then Nothing else Just (b, b-1)) 10
-- -> [10,9,8,7,6,5,4,3,2,1]
set xr to {v, v} -- (value, remainder)
set xs to {}
tell mReturn(f)
repeat -- Function applied to remainder.
set mb to |λ|(item 2 of xr)
if Nothing of mb then
exit repeat
else -- New (value, remainder) tuple,
set xr to Just of mb
-- and value appended to output list.
set end of xs to item 1 of xr
end if
end repeat
end tell
return xs
end unfoldr
 
 
-- unlines :: [String] -> String
on unlines(xs)
-- A single string formed by the intercalation
-- of a list of strings with the newline character.
set {dlm, my text item delimiters} to ¬
{my text item delimiters, linefeed}
set s to xs as text
set my text item delimiters to dlm
s
end unlines
Output:
Population counts of the first 30 powers of three:
    [1,2,2,4,3,6,6,5,6,8,9,13,10,11,14,15,11,14,14,17,17,20,19,22,16,18,24,30,25,25]

First thirty 'evil' numbers:
    [0,3,5,6,9,10,12,15,17,18,20,23,24,27,29,30,33,34,36,39,40,43,45,46,48,51,53,54,57,58]

First thirty 'odious' numbers:
    [1,2,4,7,8,11,13,14,16,19,21,22,25,26,28,31,32,35,37,38,41,42,44,47,49,50,52,55,56,59]

AutoHotkey[edit]

Loop, 30
Out1 .= PopCount(3 ** (A_Index - 1)) " "
Loop, 60
i := A_Index - 1
, PopCount(i) & 0x1 ? Out3 .= i " " : Out2 .= i " "
MsgBox, % "3^x:`t" Out1 "`nEvil:`t" Out2 "`nOdious:`t" Out3
 
PopCount(x) { ;https://en.wikipedia.org/wiki/Hamming_weight#Efficient_implementation
x -= (x >> 1) & 0x5555555555555555
, x := (x & 0x3333333333333333) + ((x >> 2) & 0x3333333333333333)
, x := (x + (x >> 4)) & 0x0f0f0f0f0f0f0f0f
return (x * 0x0101010101010101) >> 56
}
Output:
3^x:	1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25 
Evil:	0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58 
Odious:	1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59 

AWK[edit]

 
# syntax: GAWK -f POPULATION_COUNT.AWK
# converted from VBSCRIPT
BEGIN {
nmax = 30
b = 3
n = 0
bb = 1
for (i=1; i<=nmax; i++) {
list = list pop_count(bb) " "
bb *= b
}
printf("%s^n: %s\n",b,list)
for (j=0; j<=1; j++) {
c = (j == 0) ? "evil" : "odious"
i = n = 0
list = ""
while (n < nmax) {
if (pop_count(i) % 2 == j) {
n++
list = list i " "
}
i++
}
printf("%s: %s\n",c,list)
}
exit(0)
}
function pop_count(xx, xq,xr,y) {
while (xx > 0) {
xq = int(xx / 2)
xr = xx - xq * 2
if (xr == 1) { y++ }
xx = xq
}
return(y)
}
 
Output:
3^n: 1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
evil: 0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
odious: 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

C[edit]

Works with: GCC
#include <stdio.h>
 
int main() {
{
unsigned long long n = 1;
for (int i = 0; i < 30; i++) {
// __builtin_popcount() for unsigned int
// __builtin_popcountl() for unsigned long
// __builtin_popcountll() for unsigned long long
printf("%d ", __builtin_popcountll(n));
n *= 3;
}
printf("\n");
}
 
int od[30];
int ne = 0, no = 0;
printf("evil  : ");
for (int n = 0; ne+no < 60; n++) {
if ((__builtin_popcount(n) & 1) == 0) {
if (ne < 30) {
printf("%d ", n);
ne++;
}
} else {
if (no < 30) {
od[no++] = n;
}
}
}
printf("\n");
printf("odious: ");
for (int i = 0; i < 30; i++) {
printf("%d ", od[i]);
}
printf("\n");
 
return 0;
}
Output:
1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25 
evil  : 0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58 
odious: 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59 


GCC's builtin doesn't exist prior to 3.4, and the LL version is broken in 3.4 to 4.1. In 4.2+, if the platform doesn't have a good popcount instruction or isn't enabled (e.g. not compiled with -march=native), it typically emits unoptimized code which is over 2x slower than the C below. Alternative:

#if defined(__POPCNT__) && defined(__GNUC__) && (__GNUC__> 4 || (__GNUC__== 4 && __GNUC_MINOR__> 1))
#define HAVE_BUILTIN_POPCOUNTLL
#endif
static uint64_t bitcount64(uint64_t b) {
b -= (b >> 1) & 0x5555555555555555;
b = (b & 0x3333333333333333) + ((b >> 2) & 0x3333333333333333);
b = (b + (b >> 4)) & 0x0f0f0f0f0f0f0f0f;
return (b * 0x0101010101010101) >> 56;
}
/* For 32-bit, an 8-bit table may or may not be a little faster */
static uint32_t bitcount32(uint32_t b) {
b -= (b >> 1) & 0x55555555;
b = (b & 0x33333333) + ((b >> 2) & 0x33333333);
b = (b + (b >> 4)) & 0x0f0f0f0f;
return (b * 0x01010101) >> 24;
}

C#[edit]

 
using System;
using System.Linq;
 
namespace PopulationCount
{
class Program
{
private static int PopulationCount(long n)
{
string binaryn = Convert.ToString(n, 2);
return binaryn.ToCharArray().Where(t => t == '1').Count();
}
 
static void Main(string[] args)
{
Console.WriteLine("Population Counts:");
Console.Write("3^n : ");
 
int count = 0;
 
while (count < 30)
{
double n = Math.Pow(3f, (double)count);
int popCount = PopulationCount((long)n);
Console.Write(string.Format("{0} ", popCount));
count++;
}
 
Console.WriteLine();
Console.Write("Evil: ");
 
count = 0;
int i = 0;
 
while (count < 30)
{
int popCount = PopulationCount(i);
 
if (popCount % 2 == 0)
{
count++;
Console.Write(string.Format("{0} ", i));
}
 
i++;
}
 
Console.WriteLine();
Console.Write("Odious: ");
 
count = 0;
i = 0;
 
while (count < 30)
{
int popCount = PopulationCount(i);
 
if (popCount % 2 != 0)
{
count++;
Console.Write(string.Format("{0} ", i));
}
 
i++;
}
 
Console.ReadKey();
}
}
}
 
Output:
Population Counts:
3^n :   1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
Evil:   0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
Odious: 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

C++[edit]

Works with: C++11
#include <iostream>
#include <bitset>
#include <climits>
 
size_t popcount(unsigned long long n) {
return std::bitset<CHAR_BIT * sizeof n>(n).count();
}
 
int main() {
{
unsigned long long n = 1;
for (int i = 0; i < 30; i++) {
std::cout << popcount(n) << " ";
n *= 3;
}
std::cout << std::endl;
}
 
int od[30];
int ne = 0, no = 0;
std::cout << "evil  : ";
for (int n = 0; ne+no < 60; n++) {
if ((popcount(n) & 1) == 0) {
if (ne < 30) {
std::cout << n << " ";
ne++;
}
} else {
if (no < 30) {
od[no++] = n;
}
}
}
std::cout << std::endl;
std::cout << "odious: ";
for (int i = 0; i < 30; i++) {
std::cout << od[i] << " ";
}
std::cout << std::endl;
 
return 0;
}
Output:
1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25 
evil  : 0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58 
odious: 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59 


Clojure[edit]

 
(defn population-count [n]
(Long/bitCount n)) ; use Java inter-op
 
(defn exp [n pow]
(reduce * (repeat pow n)))
 
(defn evil? [n]
(even? (population-count n)))
 
(defn odious? [n]
(odd? (population-count n)))
 
;;
;; Clojure's support for generating "lazily-evaluated" infinite sequences can
;; be used to generate the requested output sets. We'll create some infinite
;; sequences, and only as many items will be computed as are "pulled" by 'take'.
;;
(defn integers []
(iterate inc 0))
 
(defn powers-of-n [n]
(map #(exp n %) (integers)))
 
(defn evil-numbers []
(filter evil? (integers)))
 
(defn odious-numbers []
(filter odious? (integers)))
Output:
(take 5 (integers))       ; ==> (0 1 2 3 4)
(take 5 (powers-of-n 3))  ; ==> (1 3 9 27 81)
(take 5 (evil-numbers))   ; ==> (0 3 5 6 9)

;; Population Counts for first 30 powers of 3:
(take 30 (map population-count (powers-of-n 3)))
; ==> (1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25)

;; First 30 'evil' numbers:
(take 30 (evil-numbers))
; ==> (0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58)

;; First 30 'odious' numbers:
(take 30 (odious-numbers))
; ==> (1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59)

Common Lisp[edit]

(format T "3^x: ~{~a ~}~%" 
(loop for i below 30
collect (logcount (expt 3 i))))
 
(multiple-value-bind
(evil odious)
(loop for i below 60
if (evenp (logcount i)) collect i into evil
else collect i into odious
finally (return (values evil odious)))
(format T "evil: ~{~a ~}~%" evil)
(format T "odious: ~{~a ~}~%" odious))
Output:
3^x: 1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25 
evil: 0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58 
odious: 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

D[edit]

void main() {
import std.stdio, std.algorithm, std.range, core.bitop;
 
enum pCount = (ulong n) => popcnt(n & uint.max) + popcnt(n >> 32);
writefln("%s\nEvil: %s\nOdious: %s",
uint.max.iota.map!(i => pCount(3L ^^ i)).take(30),
uint.max.iota.filter!(i => pCount(i) % 2 == 0).take(30),
uint.max.iota.filter!(i => pCount(i) % 2).take(30));
}
Output:
[1, 2, 2, 4, 3, 6, 6, 5, 6, 8, 9, 13, 10, 11, 14, 15, 11, 14, 14, 17, 17, 20, 19, 22, 16, 18, 24, 30, 25, 25]
Evil: [0, 3, 5, 6, 9, 10, 12, 15, 17, 18, 20, 23, 24, 27, 29, 30, 33, 34, 36, 39, 40, 43, 45, 46, 48, 51, 53, 54, 57, 58]
Odious: [1, 2, 4, 7, 8, 11, 13, 14, 16, 19, 21, 22, 25, 26, 28, 31, 32, 35, 37, 38, 41, 42, 44, 47, 49, 50, 52, 55, 56, 59]

Elixir[edit]

defmodule Population do
 
def count(n), do: count(<<n :: integer>>, 0)
 
defp count(<<>>, acc), do: acc
 
defp count(<<bit :: integer-1, rest :: bitstring>>, sum), do: count(rest, sum + bit)
 
def evil?(n), do: n >= 0 and rem(count(n),2) == 0
 
def odious?(n), do: n >= 0 and rem(count(n),2) == 1
 
end
 
IO.puts "Population count of the first thirty powers of 3:"
IO.inspect Stream.iterate(1, &(&1*3)) |> Enum.take(30) |> Enum.map(&Population.count(&1))
IO.puts "first thirty evil numbers:"
IO.inspect Stream.iterate(0, &(&1+1)) |> Stream.filter(&Population.evil?(&1)) |> Enum.take(30)
IO.puts "first thirty odious numbers:"
IO.inspect Stream.iterate(0, &(&1+1)) |> Stream.filter(&Population.odious?(&1)) |> Enum.take(30)
Output:
Population count of the first thirty powers of 3:
[1, 2, 2, 4, 3, 6, 6, 5, 6, 8, 9, 13, 10, 11, 14, 15, 11, 14, 14, 17, 17, 20, 19, 22, 16, 18, 24, 30, 25, 25]
first thirty evil numbers:
[0, 3, 5, 6, 9, 10, 12, 15, 17, 18, 20, 23, 24, 27, 29, 30, 33, 34, 36, 39, 40, 43, 45, 46, 48, 51, 53, 54, 57, 58]
first thirty odious numbers:
[1, 2, 4, 7, 8, 11, 13, 14, 16, 19, 21, 22, 25, 26, 28, 31, 32, 35, 37, 38, 41, 42, 44, 47, 49, 50, 52, 55, 56, 59]

Erlang[edit]

-module(population_count).
-export([popcount/1]).
 
-export([task/0]).
 
popcount(N) ->
popcount(N,0).
 
popcount(0,Acc) ->
Acc;
popcount(N,Acc) ->
popcount(N div 2, Acc + N rem 2).
 
threes(_,0,Acc) ->
lists:reverse(Acc);
threes(Threes,N,Acc) ->
threes(Threes * 3, N-1, [popcount(Threes)|Acc]).
 
threes(N) ->
threes(1,N,[]).
 
evil(_,0,Acc) ->
lists:reverse(Acc);
evil(N,Count,Acc) ->
case popcount(N) rem 2 of
0 ->
evil(N+1,Count-1,[N|Acc]);
1 ->
evil(N+1,Count,Acc)
end.
evil(Count) ->
evil(0,Count,[]).
 
odious(_,0,Acc) ->
lists:reverse(Acc);
odious(N,Count,Acc) ->
case popcount(N) rem 2 of
1 ->
odious(N+1,Count-1,[N|Acc]);
0 ->
odious(N+1,Count,Acc)
end.
odious(Count) ->
odious(1,Count,[]).
 
 
task() ->
io:format("Powers of 3: ~p~n",[threes(30)]),
io:format("Evil:~p~n",[evil(30)]),
io:format("Odious:~p~n",[odious(30)]).
Output:
61> population_count:task().
Powers of 3: [1,2,2,4,3,6,6,5,6,8,9,13,10,11,14,15,11,14,14,17,17,20,19,22,16,18,24,30,25,
25]
Evil:[0,3,5,6,9,10,12,15,17,18,20,23,24,27,29,30,33,34,36,39,40,43,45,46,48,
51,53,54,57,58]
Odious:[1,2,4,7,8,11,13,14,16,19,21,22,25,26,28,31,32,35,37,38,41,42,44,47,49,
50,52,55,56,59]
ok

Factor[edit]

USING: formatting kernel lists lists.lazy math math.bitwise
math.functions namespaces prettyprint.config sequences ;
 
: 3^n ( obj -- obj' ) [ 3 swap ^ bit-count ] lmap-lazy ;
: evil ( obj -- obj' ) [ bit-count even? ] lfilter ;
: odious ( obj -- obj' ) [ bit-count odd? ] lfilter ;
 
100 margin set 0 lfrom [ 3^n ] [ evil ] [ odious ] tri
[ 30 swap ltake list>array ] [email protected]
"3^n:  %u\nEvil:  %u\nOdious: %u\n" printf
Output:
3^n:    { 1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25 }
Evil:   { 0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58 }
Odious: { 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59 }

Forth[edit]

Works with: Gforth version 0.7.3
: popcnt ( n -- u)  0 swap
BEGIN dup WHILE tuck 1 AND + swap 1 rshift REPEAT
DROP ;
: odious? ( n -- t|f) popcnt 1 AND ;
: evil? ( n -- t|f) odious? 0= ;
 
CREATE A 30 ,
: task1 1 0 ." 3**i popcnt: "
BEGIN dup A @ < WHILE
over popcnt . 1+ swap 3 * swap
REPEAT DROP DROP CR ;
: task2 0 0 ." evil  : "
BEGIN dup A @ < WHILE
over evil? IF over . 1+ THEN swap 1+ swap
REPEAT DROP DROP CR ;
: task3 0 0 ." odious  : "
BEGIN dup A @ < WHILE
over odious? IF over . 1+ THEN swap 1+ swap
REPEAT DROP DROP CR ;
task1 task2 task3 BYE
Output:
3**i popcnt: 1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25 
evil       : 0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58 
odious     : 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

Fortran[edit]

Works with: Fortran version 95 and later
program population_count
implicit none
 
integer, parameter :: i64 = selected_int_kind(18)
integer(i64) :: x
integer :: i, n
 
x = 1
write(*, "(a8)", advance = "no") "3**i :"
do i = 1, 30
write(*, "(i3)", advance = "no") popcnt(x)
x = x * 3
end do
 
write(*,*)
write(*, "(a8)", advance = "no") "Evil :"
n = 0
x = 0
do while(n < 30)
if(mod(popcnt(x), 2) == 0) then
n = n + 1
write(*, "(i3)", advance = "no") x
end if
x = x + 1
end do
 
write(*,*)
write(*, "(a8)", advance = "no") "Odious :"
n = 0
x = 0
do while(n < 30)
if(mod(popcnt(x), 2) /= 0) then
n = n + 1
write(*, "(i3)", advance = "no") x
end if
x = x + 1
end do
 
contains
 
integer function popcnt(x)
integer(i64), intent(in) :: x
integer :: i
 
popcnt = 0
do i = 0, 63
if(btest(x, i)) popcnt = popcnt + 1
end do
 
end function
end program
Output:
  3**i : 1  2  2  4  3  6  6  5  6  8  9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
  Evil : 0  3  5  6  9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
Odious : 1  2  4  7  8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

Free Pascal[edit]

The system unit in the RTL (run-time library) shipped with every FPC (Free Pascal compiler) distribution contains the function popCnt. It accepts one integer parameter and is defined for all unsigned integer types. Therefore its implementation is skipped.

program populationCount(input, output, stdErr);
var
// general advice: iterator variables are _signed_
iterator: int64;
// the variable we’d like to count the set bits in
number: qWord;
// how many evil numbers we’ve already found
evilCount: int64;
// odious numbers
odiousNumber: array[1..30] of qWord;
odiousIterator: int64;
begin
// population count for powers of three
for iterator := 0 to 29 do
begin
number := round(exp(ln(3) * iterator));
write(popCnt(number):3);
end;
writeLn();
 
// evil numbers
// (while preserving calculated odious numbers for next sub-task)
evilCount := 0;
odiousIterator := low(odiousNumber);
 
// for-loop: because we (pretend to) don’t know,
// when and where we’ve found the first 30 numbers of each
for iterator := 0 to high(iterator) do
begin
// implicit typecast: popCnt only accepts _un_-signed integers
number := iterator;
if odd(popCnt(number)) then
begin
if odiousIterator <= high(odiousNumber) then
begin
odiousNumber[odiousIterator] := number;
inc(odiousIterator);
end;
end
else
begin
if evilCount < 30 then
begin
write(number:20);
inc(evilCount);
end;
end;
 
if evilCount + odiousIterator > 60 then
begin
break;
end;
end;
writeLn();
 
// odious numbers
for number in odiousNumber do
begin
write(number:20);
end;
writeLn();
end.
Output:
  1  2  2  4  3  6  6  5  6  8  9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
                   0                   3                   5                   6                   9                  10                  12                  15                  17                  18                  20                  23                  24                  27                  29                  30                  33                  34                  36                  39                  40                  43                  45                  46                  48                  51                  53                  54                  57                  58
                   1                   2                   4                   7                   8                  11                  13                  14                  16                  19                  21                  22                  25                  26                  28                  31                  32                  35                  37                  38                  41                  42                  44                  47                  49                  50                  52                  55                  56                  59

Fōrmulæ[edit]

In this page you can see the solution of this task.

Fōrmulæ programs are not textual, visualization/edition of programs is done showing/manipulating structures but not text (more info). Moreover, there can be multiple visual representations of the same program. Even though it is possible to have textual representation —i.e. XML, JSON— they are intended for transportation effects more than visualization and edition.

The option to show Fōrmulæ programs and their results is showing images. Unfortunately images cannot be uploaded in Rosetta Code.

Gambas[edit]

Click this link to run this code

Public Sub Main()
Dim sEvil, sOdious As String 'To store the output for printing Evil and Odious
Dim iCount, iEvil, iOdious As Integer 'Counters
 
Print "First 30 numbers ^3\t"; 'Print title
 
For iCount = 0 To 29 'Count 30 times
Print Len(Replace(Bin(3 ^ iCount), "0", ""));; 'Get the Bin of the number, take out the '0's and the remaining
Next 'length is the Population count e.g. 3^2=9, Bin=1001, remove '0's='11', length=2
 
iCount = 0 'Reset iCount
 
Repeat 'Repeat/Until loop
If Even(Len(Replace(Bin(iCount), "0", ""))) Then 'If (as above) the result is Even then
sEvil &= Str(icount) & " " 'Add it to sEvil
Inc iEvil 'Increase iEvil
End If
If Odd(Len(Replace(Bin(iCount), "0", ""))) Then 'If (as above) the result is Odd then
sOdious &= Str(icount) & " " 'Add it to sOdious
Inc iOdious 'Increase iOdious
End If
Inc iCount 'Increase iCount
Until iEvil = 30 And iOdious = 30 'Until both iEvil and iOdious = 30 then exit the loop
 
Print "\n1st 30 Evil numbers =\t" & sEvil 'Print Evil
Print "1st 30 Odious numbers =\t" & sOdious 'Print Odious
 
End

Output:

First 30 numbers ^3     1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25 
1st 30 Evil numbers =   0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58 
1st 30 Odious numbers = 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

Go[edit]

Standard Library[edit]

As of Go 1.9, this function is in the standard Library.

package main
 
import (
"fmt"
"math/bits"
)
 
func main() {
fmt.Println("Pop counts, powers of 3:")
n := uint64(1) // 3^0
for i := 0; i < 30; i++ {
fmt.Printf("%d ", bits.OnesCount64(n))
n *= 3
}
fmt.Println()
fmt.Println("Evil numbers:")
var od [30]uint64
var ne, no int
for n = 0; ne+no < 60; n++ {
if bits.OnesCount64(n)&1 == 0 {
if ne < 30 {
fmt.Printf("%d ", n)
ne++
}
} else {
if no < 30 {
od[no] = n
no++
}
}
}
fmt.Println()
fmt.Println("Odious numbers:")
for _, n := range od {
fmt.Printf("%d ", n)
}
fmt.Println()
}
Output:
Pop counts, powers of 3:
1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25 
Evil numbers:
0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58 
Odious numbers:
1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

Implementation[edit]

Method of WP example popcount_3:

func pop64(w uint64) int {
const (
ff = 1<<64 - 1
mask1 = ff / 3
mask3 = ff / 5
maskf = ff / 17
maskp = maskf >> 3 & maskf
)
w -= w >> 1 & mask1
w = w&mask3 + w>>2&mask3
w = (w + w>>4) & maskf
return int(w * maskp >> 56)
}

Method of WP example popcount_4:

func pop64(w uint64) (c int) {
for w != 0 {
w &= w - 1
c++
}
return
}

Haskell[edit]

Works with: GHC version 7.4+
import Data.Bits (popCount)
 
printPops :: (Show a, Integral a) => String -> [a] -> IO ()
printPops title counts = putStrLn $ title ++ show (take 30 counts)
 
main :: IO ()
main = do
printPops "popcount " $ map popCount $ iterate (*3) (1 :: Integer)
printPops "evil " $ filter (even . popCount) ([0..] :: [Integer])
printPops "odious " $ filter ( odd . popCount) ([0..] :: [Integer])
Output:
popcount [1,2,2,4,3,6,6,5,6,8,9,13,10,11,14,15,11,14,14,17,17,20,19,22,16,18,24,30,25,25]
evil     [0,3,5,6,9,10,12,15,17,18,20,23,24,27,29,30,33,34,36,39,40,43,45,46,48,51,53,54,57,58]
odious   [1,2,4,7,8,11,13,14,16,19,21,22,25,26,28,31,32,35,37,38,41,42,44,47,49,50,52,55,56,59]


Or, if we want to write our own popCount, perhaps something like:

import Data.List (partition, unfoldr)
import Data.Bifoldable (biList)
import Data.Tuple (swap)
import Data.Bool (bool)
 
-- POPCOUNT -------------------------------------------------------------
popCount :: Int -> Int
popCount =
sum . unfoldr ((bool Nothing . Just . swap . flip quotRem 2) <*> (0 <))
 
-- TEST -----------------------------------------------------------------
main :: IO ()
main =
mapM_ putStrLn $
zipWith
(\k xs -> k ++ ":\n" ++ show xs ++ "\n")
["Population count of powers of 3", "evil", "odious"]
((popCount . (3 ^) <$> [0 .. 29]) :
biList (partition (even . popCount) [0 .. 59]))
Output:
Population count of powers of 3:
[1,2,2,4,3,6,6,5,6,8,9,13,10,11,14,15,11,14,14,17,17,20,19,22,16,18,24,30,25,25]

evil:
[0,3,5,6,9,10,12,15,17,18,20,23,24,27,29,30,33,34,36,39,40,43,45,46,48,51,53,54,57,58]

odious:
[1,2,4,7,8,11,13,14,16,19,21,22,25,26,28,31,32,35,37,38,41,42,44,47,49,50,52,55,56,59]

Idris[edit]

module Main
import Data.Vect
 
isOdd : (x : Int) -> Bool
isOdd x = case mod x 2 of
0 => False
1 => True
 
popcnt : Int -> Int
popcnt 0 = 0
popcnt x = case isOdd x of
False => popcnt (shiftR x 1)
True => 1 + popcnt (shiftR x 1)
 
isOdious : Int -> Bool
isOdious k = isOdd (popcnt k)
 
isEvil : Int -> Bool
isEvil k = not (isOdious k)
 
filterUnfoldN : (n : Nat) ->
(pred : Int -> Bool) -> (f : Int -> a) ->
(next : Int -> Int) -> (seed : Int) ->
Vect n a
filterUnfoldN Z pred f next seed = []
filterUnfoldN (S k) pred f next seed =
if pred seed
then (f seed) :: filterUnfoldN k pred f next (next seed)
else filterUnfoldN (S k) pred f next (next seed)
 
printCompact : (Show a) => Vect n a -> IO ()
printCompact v = putStrLn (unwords (map show (toList v)))
 
main : IO ()
main = do putStr "popcnt(3**i): "
printCompact (filterUnfoldN 30 (\_ => True) popcnt (3 *) 1)
putStr "Evil: "
printCompact (filterUnfoldN 30 isEvil id (1 +) 0)
putStr "Odious: "
printCompact (filterUnfoldN 30 isOdious id (1 +) 0)
Output:
popcnt(3**i): 1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
Evil:         0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
Odious:       1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

J[edit]

Implementation:

countPopln=: +/"1@#:
isOdd=: 1 = 2&|
isEven=: 0 = 2&|


Task:

   countPopln 3^i.30x
1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
30{.(#~ [email protected]) i. 100 NB. odd population count (aka "ODious numbers")
1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59
30{.(#~ [email protected]) i. 100 NB. even population count (aka "EVil numbers")
0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58

Java[edit]

import java.math.BigInteger;
 
public class PopCount {
public static void main(String[] args) {
{ // with int
System.out.print("32-bit integer: ");
int n = 1;
for (int i = 0; i < 20; i++) {
System.out.printf("%d ", Integer.bitCount(n));
n *= 3;
}
System.out.println();
}
{ // with long
System.out.print("64-bit integer: ");
long n = 1;
for (int i = 0; i < 30; i++) {
System.out.printf("%d ", Long.bitCount(n));
n *= 3;
}
System.out.println();
}
{ // with BigInteger
System.out.print("big integer  : ");
BigInteger n = BigInteger.ONE;
BigInteger three = BigInteger.valueOf(3);
for (int i = 0; i < 30; i++) {
System.out.printf("%d ", n.bitCount());
n = n.multiply(three);
}
System.out.println();
}
 
int[] od = new int[30];
int ne = 0, no = 0;
System.out.print("evil  : ");
for (int n = 0; ne+no < 60; n++) {
if ((Integer.bitCount(n) & 1) == 0) {
if (ne < 30) {
System.out.printf("%d ", n);
ne++;
}
} else {
if (no < 30) {
od[no++] = n;
}
}
}
System.out.println();
System.out.print("odious : ");
for (int n : od) {
System.out.printf("%d ", n);
}
System.out.println();
}
}
Output:
32-bit integer: 1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 
64-bit integer: 1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25 
big integer   : 1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25 
evil   : 0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58 
odious : 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59 

JavaScript[edit]

ES6[edit]

(() => {
'use strict';
 
// populationCount :: Int -> Int
const populationCount = n =>
// The number of non-zero bits in the binary
// representation of the integer n.
sum(unfoldr(
x => 0 < x ? (
Just(Tuple(x % 2)(Math.floor(x / 2)))
) : Nothing()
)(n));
 
// ----------------------- TEST ------------------------
// main :: IO ()
const main = () => {
const [evens, odds] = Array.from(
partition(compose(even, populationCount))(
enumFromTo(0)(59)
)
);
return [
'Population counts of the first 30 powers of three:',
` [${enumFromTo(0)(29).map(
compose(populationCount, raise(3))
).join(',')}]`,
"\nFirst thirty 'evil' numbers:",
` [${[evens.join(',')]}]`,
"\nFirst thirty 'odious' numbers:",
` [${odds.join(',')}]`
].join('\n');
};
 
 
// ----------------- GENERIC FUNCTIONS -----------------
 
// Just :: a -> Maybe a
const Just = x => ({
type: 'Maybe',
Nothing: false,
Just: x
});
 
 
// Nothing :: Maybe a
const Nothing = () => ({
type: 'Maybe',
Nothing: true,
});
 
 
// Tuple (,) :: a -> b -> (a, b)
const Tuple = a =>
b => ({
type: 'Tuple',
'0': a,
'1': b,
length: 2
});
 
 
// compose (<<<) :: (b -> c) -> (a -> b) -> a -> c
const compose = (...fs) =>
// A function defined by the right-to-left
// composition of all the functions in fs.
fs.reduce(
(f, g) => x => f(g(x)),
x => x
);
 
 
// enumFromTo :: Int -> Int -> [Int]
const enumFromTo = m =>
n => !isNaN(m) ? (
Array.from({
length: 1 + n - m
}, (_, i) => m + i)
) : enumFromTo_(m)(n);
 
 
// even :: Int -> Bool
const even = n =>
// True if n is an even number.
0 === n % 2;
 
 
// partition :: (a -> Bool) -> [a] -> ([a], [a])
const partition = p =>
// A tuple of two lists - those elements in
// xs which match p, and those which don't.
xs => ([...xs]).reduce(
(a, x) =>
p(x) ? (
Tuple(a[0].concat(x))(a[1])
) : Tuple(a[0])(a[1].concat(x)),
Tuple([])([])
);
 
 
// raise :: Num -> Int -> Num
const raise = x =>
// X to the power of n.
n => Math.pow(x, n);
 
 
// sum :: [Num] -> Num
const sum = xs =>
// The numeric sum of all values in xs.
xs.reduce((a, x) => a + x, 0);
 
 
// unfoldr :: (b -> Maybe (a, b)) -> b -> [a]
const unfoldr = f =>
v => {
const xs = [];
let xr = [v, v];
while (true) {
const mb = f(xr[1]);
if (mb.Nothing) {
return xs
} else {
xr = mb.Just;
xs.push(xr[0])
}
}
};
 
// ---
return main();
})();
Output:
Population counts of the first 30 powers of three:
    [1,2,2,4,3,6,6,5,6,8,9,13,10,11,14,15,11,14,14,17,17,20,19,22,16,18,24,30,25,25]

First thirty 'evil' numbers:
    [0,3,5,6,9,10,12,15,17,18,20,23,24,27,29,30,33,34,36,39,40,43,45,46,48,51,53,54,57,58]

First thirty 'odious' numbers:
    [1,2,4,7,8,11,13,14,16,19,21,22,25,26,28,31,32,35,37,38,41,42,44,47,49,50,52,55,56,59]

jq[edit]

Works with: jq version 1.4
def popcount: 
def bin: recurse( if . == 0 then empty else ./2 | floor end ) % 2;
[bin] | add;
 
def firstN(count; condition):
if count > 0 then
if condition then ., (1+.| firstN(count-1; condition))
else (1+.) | firstN(count; condition)
end
else empty
end;
 
def task:
def pow(n): . as $m | reduce range(0;n) as $i (1; . * $m);
 
"The pop count of the first thirty powers of 3:",
[range(0;30) as $n | 3 | pow($n) | popcount],
 
"The first thirty evil numbers:",
[0 | firstN(30; (popcount % 2) == 0)],
 
"The first thirty odious numbers:",
[0 | firstN(30; (popcount % 2) == 1)]
;
 
task
Output:
$ jq -n -r -c -f Population_count.jq
The pop count of the first thirty powers of 3:
[1,2,2,4,3,6,6,5,6,8,9,13,10,11,14,15,11,14,14,17,17,20,19,22,16,18,24,30,25,25]
The first thirty evil numbers:
[0,3,5,6,9,10,12,15,17,18,20,23,24,27,29,30,33,34,36,39,40,43,45,46,48,51,53,54,57,58]
The first thirty odious numbers:
[1,2,4,7,8,11,13,14,16,19,21,22,25,26,28,31,32,35,37,38,41,42,44,47,49,50,52,55,56,59]

Julia[edit]

popcount(n) = sum(digits(n, base=2))
 
println("First 3 ^ i, up to 29 pop. counts: ", join((popcount(3 ^ n) for n in 0:29), ", "))
println("Evil numbers: ", join(filter(x -> iseven(popcount(x)), 0:59), ", "))
println("Odious numbers: ", join(filter(x -> isodd(popcount(x)), 0:59), ", "))
Output:
First 3 ^ i, up to 29 pop. counts: 1, 2, 2, 4, 3, 6, 6, 5, 6, 8, 9, 13, 10, 11, 14, 15, 11, 14, 14, 17, 17, 20, 19, 22, 16, 18, 24, 30, 25, 25
Evil numbers: 0, 3, 5, 6, 9, 10, 12, 15, 17, 18, 20, 23, 24, 27, 29, 30, 33, 34, 36, 39, 40, 43, 45, 46, 48, 51, 53, 54, 57, 58
Odious numbers: 1, 2, 4, 7, 8, 11, 13, 14, 16, 19, 21, 22, 25, 26, 28, 31, 32, 35, 37, 38, 41, 42, 44, 47, 49, 50, 52, 55, 56, 59

Kotlin[edit]

// version 1.0.6
 
fun popCount(n: Long) = when {
n < 0L -> throw IllegalArgumentException("n must be non-negative")
else -> java.lang.Long.bitCount(n)
}
 
fun main(args: Array<String>) {
println("The population count of the first 30 powers of 3 are:")
var pow3 = 1L
for (i in 1..30) {
print("${popCount(pow3)} ")
pow3 *= 3L
}
println("\n")
println("The first thirty evil numbers are:")
var count = 0
var i = 0
while (true) {
val pc = popCount(i.toLong())
if (pc % 2 == 0) {
print("$i ")
if (++count == 30) break
}
i++
}
println("\n")
println("The first thirty odious numbers are:")
count = 0
i = 1
while (true) {
val pc = popCount(i.toLong())
if (pc % 2 == 1) {
print("$i ")
if (++count == 30) break
}
i++
}
println()
}
Output:
The population count of the first 30 powers of 3 are:
1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25

The first thirty evil numbers are:
0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58

The first thirty odious numbers are:
1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

Lua[edit]

-- Take decimal number, return binary string
function dec2bin (n)
local bin, bit = ""
while n > 0 do
bit = n % 2
n = math.floor(n / 2)
bin = bit .. bin
end
return bin
end
 
-- Take decimal number, return population count as number
function popCount (n)
local bin, count = dec2bin(n), 0
for pos = 1, bin:len() do
if bin:sub(pos, pos) == "1" then count = count + 1 end
end
return count
end
 
-- Implement task requirements
function firstThirty (mode)
local numStr, count, n, remainder = "", 0, 0
if mode == "Evil" then remainder = 0 else remainder = 1 end
while count < 30 do
if mode == "3^x" then
numStr = numStr .. popCount(3 ^ count) .. " "
count = count + 1
else
if popCount(n) % 2 == remainder then
numStr = numStr .. n .. " "
count = count + 1
end
n = n + 1
end
end
print(mode .. ":" , numStr)
end
 
-- Main procedure
firstThirty("3^x")
firstThirty("Evil")
firstThirty("Odious")
Output:
3^x:    1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
Evil:   0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
Odious: 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

Mathematica[edit]

popcount[n_Integer] := IntegerDigits[n, 2] // Total
Print["population count of powers of 3"]
popcount[#] & /@ (3^Range[0, 30])
(*******)
evilQ[n_Integer] := popcount[n] // EvenQ
evilcount = 0;
evillist = {};
i = 0;
While[evilcount < 30,
If[evilQ[i], AppendTo[evillist, i]; evilcount++];
i++
]
Print["first thirty evil numbers"]
evillist
(*******)
odiousQ[n_Integer] := popcount[n] // OddQ
odiouscount = 0;
odiouslist = {};
i = 0;
While[odiouscount < 30,
If[odiousQ[i], AppendTo[odiouslist, i]; odiouscount++];
i++
]
Print["first thirty odious numbers"]
odiouslist
Output:
population count of powers of 3
{1, 2, 2, 4, 3, 6, 6, 5, 6, 8, 9, 13, 10, 11, 14, 15, 11, 14, 14, 17, 17, 20, 19, 22, 16, 18, 24, 30, 25, 25, 25}
first thirty evil numbers
{0, 3, 5, 6, 9, 10, 12, 15, 17, 18, 20, 23, 24, 27, 29, 30, 33, 34, 36, 39, 40, 43, 45, 46, 48, 51, 53, 54, 57, 58}
first thirty odious numbers
{1, 2, 4, 7, 8, 11, 13, 14, 16, 19, 21, 22, 25, 26, 28, 31, 32, 35, 37, 38, 41, 42, 44, 47, 49, 50, 52, 55, 56, 59}

min[edit]

Works with: min version 0.19.3
(2 over over mod 'div dip) :divmod2
 
(
 :n () =list
(n 0 >) (n divmod2 list append #list @n) while
list (1 ==) filter size
) :pop-count
 
(:n 0 () (over swap append 'succ dip) n times) :iota
 
"3^n: " print! 30 iota (3 swap pow int pop-count) map puts!
60 iota (pop-count odd?) partition
"Evil: " print! puts! "Odious: " print! puts!
Output:
3^n:    (1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25)
Evil:   (0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58)
Odious: (1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59)

Nim[edit]

import bitops
import strformat
 
var n = 1
write(stdout, "3^x  :")
for i in 0..<30:
write(stdout, fmt"{popcount(n):2} ")
n *= 3
 
var od: array[30, int]
var ne, no = 0
n = 0
write(stdout, "\nevil  :")
while ne + no < 60:
if (popcount(n) and 1) == 0:
if ne < 30:
write(stdout, fmt"{n:2} ")
inc ne
else:
if no < 30:
od[no] = n
inc no
inc n
 
write(stdout, "\nodious:")
for i in 0..<30:
write(stdout, fmt"{od[i]:2} ")
3^x   : 1  2  2  4  3  6  6  5  6  8  9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25 
evil  : 0  3  5  6  9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58 
odious: 1  2  4  7  8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59 

Oforth[edit]

: popcount(n)
0 while ( n ) [ n isOdd + n bitRight(1) ->n ] ;
 
: test
| i count |
30 seq map(#[ 3 swap 1- pow ]) map(#popcount) println
 
0 ->count
0 while( count 30 <> ) [ dup popcount isEven ifTrue: [ dup . count 1+ ->count ] 1+ ] drop printcr
 
0 ->count
0 while( count 30 <> ) [ dup popcount isOdd ifTrue: [ dup . count 1+ ->count ] 1+ ] drop ;
Output:
>test
[1, 2, 2, 4, 3, 6, 6, 5, 6, 8, 9, 13, 10, 11, 14, 15, 11, 14, 14, 17, 17, 20, 19, 22, 16, 18, 24, 30, 25, 25]
0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59 ok

PARI/GP[edit]

vector(30,n,hammingweight(3^(n-1)))
od=select(n->hammingweight(n)%2,[0..100]); ev=setminus([0..100],od);
ev[1..30]
od[1..30]
Output:
%1 = [1, 2, 2, 4, 3, 6, 6, 5, 6, 8, 9, 13, 10, 11, 14, 15, 11, 14, 14, 17, 17, 20, 19, 22, 16, 18, 24, 30, 25, 25]
%2 = [0, 3, 5, 6, 9, 10, 12, 15, 17, 18, 20, 23, 24, 27, 29, 30, 33, 34, 36, 39, 40, 43, 45, 46, 48, 51, 53, 54, 57, 58]
%3 = [1, 2, 4, 7, 8, 11, 13, 14, 16, 19, 21, 22, 25, 26, 28, 31, 32, 35, 37, 38, 41, 42, 44, 47, 49, 50, 52, 55, 56, 59]

Pascal[edit]

Works with: freepascal

Like Ada a unit is used.

unit popcount;
{$IFDEF FPC}
{$MODE DELPHI}
{$OPTIMIZATION ON,ASMCSE,CSE,PEEPHOLE}
{$Smartlink OFF}
{$ENDIF}
 
interface
function popcnt(n:Uint64):integer;overload;
function popcnt(n:Uint32):integer;overload;
function popcnt(n:Uint16):integer;overload;
function popcnt(n:Uint8):integer;overload;
 
implementation
const
//K1 = $0101010101010101;
K33 = $3333333333333333;
K55 = $5555555555555555;
KF1 = $0F0F0F0F0F0F0F0F;
KF2 = $00FF00FF00FF00FF;
KF4 = $0000FFFF0000FFFF;
KF8 = $00000000FFFFFFFF;
{
function popcnt64(n:Uint64):integer;
begin
n := n- (n shr 1) AND K55;
n := (n AND K33)+ ((n shr 2) AND K33);
n := (n + (n shr 4)) AND KF1;
n := (n*k1) SHR 56;
result := n;
end;
}

function popcnt(n:Uint64):integer;overload;
// on Intel Haswell 2x faster for fpc 32-Bit
begin
n := (n AND K55)+((n shr 1) AND K55);
n := (n AND K33)+((n shr 2) AND K33);
n := (n AND KF1)+((n shr 4) AND KF1);
n := (n AND KF2)+((n shr 8) AND KF2);
n := (n AND KF4)+((n shr 16) AND KF4);
n := (n AND KF8)+ (n shr 32);
result := n;
end;
 
function popcnt(n:Uint32):integer;overload;
var
c,b : NativeUint;
begin
b := n;
c := (b shr 1) AND NativeUint(K55); b := (b AND NativeUint(K55))+C;
c := ((b shr 2) AND NativeUint(K33));b := (b AND NativeUint(K33))+C;
c:= ((b shr 4) AND NativeUint(KF1)); b := (b AND NativeUint(KF1))+c;
c := ((b shr 8) AND NativeUint(KF2));b := (b AND NativeUint(KF2))+c;
c := b shr 16; b := (b AND NativeUint(KF4))+ C;
result := b;
end;
 
function popcnt(n:Uint16):integer;overload;
var
c,b : NativeUint;
begin
b := n;
c := (b shr 1) AND NativeUint(K55); b := (b AND NativeUint(K55))+C;
c :=((b shr 2) AND NativeUint(K33)); b := (b AND NativeUint(K33))+C;
c:= ((b shr 4) AND NativeUint(KF1)); b := (b AND NativeUint(KF1))+c;
c := b shr 8; b := (b AND NativeUint(KF2))+c;
result := b;
end;
 
function popcnt(n:Uint8):integer;overload;
var
c,b : NativeUint;
begin
b := n;
c := (b shr 1) AND NativeUint(K55); b := (b AND NativeUint(K55))+C;
c :=((b shr 2) AND NativeUint(K33));b := (b AND NativeUint(K33))+C;
c:= b shr 4;
result := (b AND NativeUint(KF1))+c;
end;
 
Begin
End.

The program

program pcntTest;
uses
sysutils,popCount;
 
function Odious(n:Uint32):boolean;inline;
Begin
Odious := boolean(PopCnt(n) AND 1)
end;
 
function EvilNumber(n:Uint32):boolean;inline;
begin
EvilNumber := boolean(NOT(PopCnt(n)) AND 1);
end;
 
var
s : String;
i : Uint64;
k : LongWord;
Begin
s :='PopCnt 3^i  :';
i:= 1;
For k := 1 to 30 do
Begin
s := s+InttoStr(PopCnt(i)) +' ';
i := 3*i;
end;
writeln(s);writeln;
 
s:='Evil numbers  :';i := 0;k := 0;
repeat
IF EvilNumber(i) then
Begin
inc(k);s := s+InttoStr(i) +' ';
end;
inc(i);
until k = 30;
writeln(s);writeln;s:='';
 
 
s:='Odious numbers :';i := 0;k := 0;
repeat
IF Odious(i) then
Begin
inc(k);s := s+InttoStr(i) +' ';
end;
inc(i);
until k = 30;
writeln(s);
end.
Output
PopCnt 3^i     :1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
Evil numbers   :0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
Odious numbers :1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

Some processors define the card function, which can be used in conjunction with sets:

var
i: integer;
f: set of 0..(bitSizeOf(i)-1) absolute i; // same address as i, but different interpretation
begin
writeLn(card(f));
end;

Perl[edit]

Translation of: Raku

We'll emulate infinite lists with closures.

use strict;
use warnings;
 
sub population_count {
my $n = shift;
die "argument can't be negative" if $n < 0;
my $c;
for ($c = 0; $n; $n >>= 1) {
$c += $n & 1;
}
$c;
}
 
print join ' ', map { population_count(3**$_) } 0 .. 30 - 1;
print "\n";
sub evil {
my $i = 0;
sub { $i++ while population_count($i) % 2; $i++ }
}
sub odious {
my $i = 0;
sub { $i++ until population_count($i) % 2; $i++ }
}
 
my ($evil, $odious) = (evil, odious);
my (@evil, @odious);
for (1 .. 30) {
push @evil, $evil->();
push @odious, $odious->();
}
 
printf "Evil  : %s\n", join ' ', @evil;
printf "Odious: %s\n", join ' ', @odious;
Output:
1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
Evil  : 0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
Odious: 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59


A faster population count can be done with pack/unpack:

say unpack("%b*",pack "J*", 1234567); # J = UV

Various modules can also perform a population count, with the first of these being faster than the pack/unpack builtins. The first three easily support bigints, the last will with some adjustment.

use ntheory qw/hammingweight/;
say hammingweight(1234567);
 
use Math::GMPz qw/Rmpz_popcount/;
say Rmpz_popcount(Math::GMPz->new(1234567));
 
use Math::BigInt;
say 0 + (Math::BigInt->new(1234567)->as_bin() =~ tr/1//);
 
use Bit::Vector;
say Bit::Vector->new_Dec(64,1234567)->Norm;

Phix[edit]

function pop_count(atom n)
if n<0 then ?9/0 end if
integer res = 0
while n!=0 do
res += and_bits(n,1)
n = floor(n/2)
end while
return res
end function
 
sequence s = {}
for i=0 to 29 do
s &= pop_count(power(3,i))
end for
puts(1,"3^x pop_counts:") ?s
 
procedure eo(integer b0, string name)
integer k=0, l=1
while l<=30 do
if and_bits(pop_count(k),1)=b0 then
s[l] = k
l += 1
end if
k += 1
end while
puts(1,name&" numbers:") ?s
end procedure
eo(0," evil")
eo(1,"odious")
Output:
3^x pop_counts:{1,2,2,4,3,6,6,5,6,8,9,13,10,11,14,15,11,14,14,17,17,20,19,22,16,18,24,30,25,25}
  evil numbers:{0,3,5,6,9,10,12,15,17,18,20,23,24,27,29,30,33,34,36,39,40,43,45,46,48,51,53,54,57,58}
odious numbers:{1,2,4,7,8,11,13,14,16,19,21,22,25,26,28,31,32,35,37,38,41,42,44,47,49,50,52,55,56,59}

PHP[edit]

 
function convertToBinary($integer) {
$binary = "";
 
do {
$quotient = (int) ($integer / 2);
$binary .= $integer % 2;
$integer = $quotient;
} while ($quotient > 0);
 
return $binary;
}
 
function getPopCount($integer) {
$binary = convertToBinary($integer);
$offset = 0;
$popCount = 0;
 
do {
$pos = strpos($binary, "1", $offset);
if($pos !== FALSE) $popCount++;
$offset = $pos + 1;
} while ($pos !== FALSE);
 
return $popCount;
}
 
function print3PowPopCounts() {
for ($p = 0; $p < 30; $p++) {
echo " " . getPopCount(3 ** $p);
}
}
 
function printFirst30Evil() {
$counter = 0;
$pops = 0;
 
while ($pops < 30) {
$popCount = getPopCount($counter);
if ($popCount % 2 == 0) {
echo " " . $counter;
$pops++;
}
$counter++;
}
}
 
function printFirst30Odious() {
$counter = 1;
$pops = 0;
 
while ($pops < 30) {
$popCount = getPopCount($counter);
if ($popCount % 2 != 0) {
echo " " . $counter;
$pops++;
}
$counter++;
}
}
 
echo "3 ^ x pop counts:";
print3PowPopCounts();
 
echo "\nfirst 30 evil numbers:";
printFirst30Evil();
 
echo "\nfirst 30 odious numbers:";
printFirst30Odious();
 
Output:
03 ^ x pop counts: 1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
first 30 evil numbers: 0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
first 30 odious numbers: 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

PicoLisp[edit]

(de popz (N)
(cnt
'((N) (= "1" N))
(chop (bin N)) ) )
 
(println
'pops:
(mapcar
'((N) (popz (** 3 N)))
(range 0 29) ) )
(setq N -1)
(println
'evil:
(make
(for (C 0 (> 30 C))
(unless (bit? 1 (popz (inc 'N)))
(link N)
(inc 'C) ) ) ) )
(setq N -1)
(println
'odio:
(make
(for (C 0 (> 30 C))
(when (bit? 1 (popz (inc 'N)))
(link N)
(inc 'C) ) ) ) )
Output:
pops: (1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25)
evil: (0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58)
odio: (1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59)

PowerShell[edit]

 
function pop-count($n) {
(([Convert]::ToString($n, 2)).toCharArray() | where {$_ -eq '1'}).count
}
"pop_count 3^n: $(1..29 | foreach -Begin {$n = 1; (pop-count $n)} -Process {$n = 3*$n; (pop-count $n)} )"
"even pop_count: $($m = $n = 0; while($m -lt 30) {if(0 -eq ((pop-count $n)%2)) {$m += 1; $n}; $n += 1} )"
"odd pop_count: $($m = $n = 0; while($m -lt 30) {if(1 -eq ((pop-count $n)%2)) {$m += 1; $n}; $n += 1} )"
 

Output:

pop_count 3^n: 1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
even pop_count: 0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
odd pop_count: 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

Python[edit]

Procedural[edit]

>>> def popcount(n): return bin(n).count("1")
...
>>> [popcount(3**i) for i in range(30)]
[1, 2, 2, 4, 3, 6, 6, 5, 6, 8, 9, 13, 10, 11, 14, 15, 11, 14, 14, 17, 17, 20, 19, 22, 16, 18, 24, 30, 25, 25]
>>> evil, odious, i = [], [], 0
>>> while len(evil) < 30 or len(odious) < 30:
... p = popcount(i)
... if p % 2: odious.append(i)
... else: evil.append(i)
... i += 1
...
>>> evil[:30]
[0, 3, 5, 6, 9, 10, 12, 15, 17, 18, 20, 23, 24, 27, 29, 30, 33, 34, 36, 39, 40, 43, 45, 46, 48, 51, 53, 54, 57, 58]
>>> odious[:30]
[1, 2, 4, 7, 8, 11, 13, 14, 16, 19, 21, 22, 25, 26, 28, 31, 32, 35, 37, 38, 41, 42, 44, 47, 49, 50, 52, 55, 56, 59]
>>>

Composition of pure functions[edit]

Works with: Python version 3
'''Population count'''
 
from functools import reduce
 
 
# popCount :: Int -> Int
def popCount(n):
'''The count of non-zero digits in the binary
representation of the positive integer n.'''

def go(x):
return Just(divmod(x, 2)) if 0 < x else Nothing()
return sum(unfoldl(go)(n))
 
 
# -------------------------- TEST --------------------------
def main():
'''Tests'''
 
print('Population count of first 30 powers of 3:')
print(' ' + showList(
[popCount(pow(3, x)) for x in enumFromTo(0)(29)]
))
 
evilNums, odiousNums = partition(
compose(even, popCount)
)(enumFromTo(0)(59))
 
print("\nFirst thirty 'evil' numbers:")
print(' ' + showList(evilNums))
 
print("\nFirst thirty 'odious' numbers:")
print(' ' + showList(odiousNums))
 
 
# ------------------------ GENERIC -------------------------
 
# Just :: a -> Maybe a
def Just(x):
'''Constructor for an inhabited Maybe (option type) value.
Wrapper containing the result of a computation.
'''

return {'type': 'Maybe', 'Nothing': False, 'Just': x}
 
 
# Nothing :: Maybe a
def Nothing():
'''Constructor for an empty Maybe (option type) value.
Empty wrapper returned where a computation is not possible.
'''

return {'type': 'Maybe', 'Nothing': True}
 
 
# compose :: ((a -> a), ...) -> (a -> a)
def compose(*fs):
'''Composition, from right to left,
of a series of functions.
'''

def go(f, g):
def fg(x):
return f(g(x))
return fg
return reduce(go, fs, lambda x: x)
 
 
# enumFromTo :: Int -> Int -> [Int]
def enumFromTo(m):
'''Enumeration of integer values [m..n]'''
return lambda n: range(m, 1 + n)
 
 
# even :: Int -> Bool
def even(x):
'''True if x is an integer
multiple of two.
'''

return 0 == x % 2
 
 
# partition :: (a -> Bool) -> [a] -> ([a], [a])
def partition(p):
'''The pair of lists of those elements in xs
which respectively do, and don't
satisfy the predicate p.
'''

 
def go(a, x):
ts, fs = a
return (ts + [x], fs) if p(x) else (ts, fs + [x])
return lambda xs: reduce(go, xs, ([], []))
 
 
# showList :: [a] -> String
def showList(xs):
'''Stringification of a list.'''
return '[' + ','.join(repr(x) for x in xs) + ']'
 
 
# unfoldl(lambda x: Just(((x - 1), x)) if 0 != x else Nothing())(10)
# -> [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
# unfoldl :: (b -> Maybe (b, a)) -> b -> [a]
def unfoldl(f):
'''Dual to reduce or foldl.
Where these reduce a list to a summary value, unfoldl
builds a list from a seed value.
Where f returns Just(a, b), a is appended to the list,
and the residual b is used as the argument for the next
application of f.
When f returns Nothing, the completed list is returned.
'''

def go(v):
x, r = v, v
xs = []
while True:
mb = f(x)
if mb.get('Nothing'):
return xs
else:
x, r = mb.get('Just')
xs.insert(0, r)
return xs
return go
 
 
# MAIN ---
if __name__ == '__main__':
main()
Output:
Population count of first 30 powers of 3:
    [1,2,2,4,3,6,6,5,6,8,9,13,10,11,14,15,11,14,14,17,17,20,19,22,16,18,24,30,25,25]

First thirty 'evil' numbers:
    [0,3,5,6,9,10,12,15,17,18,20,23,24,27,29,30,33,34,36,39,40,43,45,46,48,51,53,54,57,58]

First thirty 'odious' numbers:
    [1,2,4,7,8,11,13,14,16,19,21,22,25,26,28,31,32,35,37,38,41,42,44,47,49,50,52,55,56,59]

Racket[edit]

#lang racket
;; Positive version from "popcount_4" in:
;; https://en.wikipedia.org/wiki/Hamming_weight#Efficient_implementation
;; negative version follows R6RS definition documented in:
;; http://docs.racket-lang.org/r6rs/r6rs-lib-std/r6rs-lib-Z-H-12.html?q=bitwise-bit#node_idx_1074
(define (population-count n)
(if (negative? n)
(bitwise-not (population-count (bitwise-not n)))
(let inr ((x n) (rv 0))
(if (= x 0) rv (inr (bitwise-and x (sub1 x)) (add1 rv))))))
 
(define (evil? x)
(and (not (negative? x))
(even? (population-count x))))
 
(define (odious? x)
(and (positive? x)
(odd? (population-count x))))
 
(define tasks
(list
"display the pop count of the 1st thirty powers of 3 (3^0, 3^1, 3^2, 3^3, 3^4, ...)."
(for/list ((i (in-range 30))) (population-count (expt 3 i)))
"display the 1st thirty evil numbers."
(for/list ((_ (in-range 30)) (e (sequence-filter evil? (in-naturals)))) e)
"display the 1st thirty odious numbers."
(for/list ((_ (in-range 30)) (o (sequence-filter odious? (in-naturals)))) o)))
 
(for-each displayln tasks)
 
(module+ test
(require rackunit)
(check-equal?
(for/list ((p (sequence-map population-count (in-range 16)))) p)
'(0 1 1 2 1 2 2 3 1 2 2 3 2 3 3 4))
(check-true (evil? 0) "0 has just *got* to be evil")
(check-true (evil? #b011011011) "six bits... truly evil")
(check-false (evil? #b1011011011) "seven bits, that's odd!")
(check-true (odious? 1) "the least odious number")
(check-true (odious? #b1011011011) "seven (which is odd) bits")
(check-false (odious? #b011011011) "six bits... is evil"))
Output:
display the pop count of the 1st thirty powers of 3 (3^0, 3^1, 3^2, 3^3, 3^4, ...).
(1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25)
display the 1st thirty evil numbers.
(0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58)
display the 1st thirty odious numbers.
(1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59)

Raku[edit]

(formerly Perl 6)

sub population-count(Int $n where * >= 0) { [+] $n.base(2).comb }
 
say map &population-count, 3 «**« ^30;
say "Evil: ", (grep { population-count($_) %% 2 }, 0 .. *)[^30];
say "Odious: ", (grep { population-count($_) % 2 }, 0 .. *)[^30];
Output:
1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
Evil: 0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
Odious: 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

That's the convenient way to write it, but the following avoids string processing and is therefore about twice as fast:

sub population-count(Int $n is copy where * >= 0) { 
loop (my $c = 0; $n; $n +>= 1) {
$c += $n +& 1;
}
$c;
}

REXX[edit]

The   pop count   is used in some encryption/decryption methods;   a major mainframe manufacturer was coerced  
(many years ago)   to add a hardware instruction to count the bits in a (binary) integer.

/*REXX program counts the number of "one" bits in the binary version of a decimal number*/
/*─────────────────── and also generates a specific number of EVIL and ODIOUS numbers.*/
parse arg N B . /*get optional arguments from the C.L. */
if N=='' | N=="," then N= 30 /*N not specified? Then use default. */
if B=='' | B=="," then B= 3 /*B " " " " " */
numeric digits 2000 /*be able to handle gihugeic numbers.*/
numeric digits max(20, length(B**N) ) /*whittle the precision down to size.*/
$= /* [↑] a little calculation for sizing*/
do j=0 for N; $= $ popCount(B**j) /*generate N popCounts for some powers.*/
end /*j*/ /* [↑] append popCount to the $ list. */
/* [↓] display popCounts of "3" powers*/
call showList 'popCounts of the powers of' B /*display the list with a header/title.*/
 
do j=0 until #>=N /*generate N evil numbers. */
if popCount(j) // 2 then iterate /*if odd population count, skip it. */
#= # + 1; $= $ j /*bump evil # count; add it to $ list.*/
end /*j*/ /* [↑] build a list of evil numbers. */
/* [↓] display the evil number list. */
call showList 'evil numbers' /*display the $ list with a header. */
 
do j=0 until #>=N /*generate N odious numbers. */
if popCount(j) // 2 ==0 then iterate /*if even population count, then skip. */
#= # + 1; $=$ j /*bump odious # count; add to $ list. */
end /*j*/ /* [↑] build a list of odious numbers.*/
/* [↓] display the odious number list.*/
call showList 'odious numbers' /*display the $ list with a header. */
exit /*stick a fork in it, we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
d2b: return word( strip( x2b( d2x( arg(1) ) ), 'L', 0) 0, 1) /*dec ──► bin.*/
popCount: return length( space( translate( d2b(arg(1) ), , 0), 0) ) /*count ones. */
showList: say; say 'The 1st' N arg(1)":"; say strip($); #= 0; $=; return
output   when using the default input:
The 1st 30 popCounts of the powers of 3:
1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25

The 1st 30 evil numbers:
0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58

The 1st 30 odious numbers:
1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

Ring[edit]

 
# Project : Population count
 
load "stdlib.ring"
n = 0
neven = 0
nodd = 0
binodd = []
bineven = []
binpow = []
while true
n = n + 1
numb = 0
bin = binarydigits(n)
for nr = 1 to len(bin)
if bin[nr] = "1"
numb = numb + 1
ok
next
if numb % 2 = 0
neven = neven + 1
if neven < 31
add(bineven, n)
ok
else
nodd = nodd + 1
if nodd < 31
add(binodd, n)
ok
ok
if neven > 30 and nodd > 30
exit
ok
end
 
see "3^x:" + nl
for n = 0 to 29
numb = 0
bin = binarydigits(pow(3,n))
for nr = 1 to len(bin)
if bin[nr] = "1"
numb = numb + 1
ok
next
add(binpow, numb)
next
showarray(binpow)
see nl
 
see "Evil numbers :" + nl
showarray(bineven)
see nl
see "Odious numbers:" + nl
showarray(binodd)
see nl
 
func showarray(vect)
see "["
svect = ""
for n = 1 to len(vect)
svect = svect + vect[n] + ", "
next
svect = left(svect, len(svect) - 2)
see svect
see "]" + nl
 

Output:

3^x:
[1, 2, 2, 4, 3, 6, 6, 5, 6, 8, 9, 13, 10, 11, 14, 15, 11, 14, 14, 17, 17, 20, 19, 22, 16, 18, 24, 30, 25, 25]

Evil numbers :
[3, 4, 5, 6, 9, 10, 12, 15, 16, 17, 18, 20, 23, 24, 27, 29, 30, 33, 34, 36, 39, 40, 43, 45, 46, 48, 51, 53, 54, 57]

Odious numbers:
[1, 2, 7, 8, 11, 13, 14, 19, 21, 22, 25, 26, 28, 31, 32, 35, 37, 38, 41, 42, 44, 47, 49, 50, 52, 55, 56, 59, 61, 62]

Ruby[edit]

Demonstrating lazy enumerators.

class Integer
 
def popcount
digits(2).count(1) #pre Ruby 2.4: self.to_s(2).count("1")
end
 
def evil?
self >= 0 && popcount.even?
end
 
end
 
puts "Powers of 3:", (0...30).map{|n| (3**n).popcount}.join(' ')
puts "Evil:" , 0.step.lazy.select(&:evil?).first(30).join(' ')
puts "Odious:", 0.step.lazy.reject(&:evil?).first(30).join(' ')
Output:

Powers of 3: 1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25 Evil: 0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58 Odious: 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

Rust[edit]

fn main() {
let mut num = 1u64;
let mut vec = Vec::new();
for _ in 0..30 {
vec.push(num.count_ones());
num *= 3;
}
println!("pop count of 3^0, 3^1 ... 3^29:\n{:?}",vec);
let mut even = Vec::new();
let mut odd = Vec::new();
num = 1;
while even.len() < 30 || odd.len() < 30 {
match 0 == num.count_ones()%2 {
true if even.len() < 30 => even.push(num),
false if odd.len() < 30 => odd.push(num),
_ => {}
}
num += 1;
}
println!("\nFirst 30 even pop count:\n{:?}",even);
println!("\nFirst 30 odd pop count:\n{:?}",odd);
}
Output:
pop count of 3^0, 3^1 ... 3^29:
[1, 2, 2, 4, 3, 6, 6, 5, 6, 8, 9, 13, 10, 11, 14, 15, 11, 14, 14, 17, 17, 20, 19, 22, 16, 18, 24, 30, 25, 25]

First 30 even pop count:
[3, 5, 6, 9, 10, 12, 15, 17, 18, 20, 23, 24, 27, 29, 30, 33, 34, 36, 39, 40, 43, 45, 46, 48, 51, 53, 54, 57, 58, 60]

First 30 odd pop count:
[1, 2, 4, 7, 8, 11, 13, 14, 16, 19, 21, 22, 25, 26, 28, 31, 32, 35, 37, 38, 41, 42, 44, 47, 49, 50, 52, 55, 56, 59]

Scala[edit]

Output:
See it yourself by running in your browser either by ScalaFiddle (ES aka JavaScript, non JVM) or Scastie (remote JVM).
Works with: Scala version 2.13
import java.lang.Long.bitCount
 
object PopCount extends App {
val nNumber = 30
 
def powersThree(start: Long): LazyList[Long] = start #:: powersThree(start * 3L)
 
println("Population count of 3ⁿ :")
println(powersThree(1L).map(bitCount).take(nNumber).mkString(", "))
 
def series(start: Long): LazyList[Long] = start #:: series(start + 1L)
 
println("Evil numbers:")
println(series(0L).filter(bitCount(_) % 2 == 0).take(nNumber).mkString(", "))
 
println("Odious numbers:")
println(series(0L).filter(bitCount(_) % 2 != 0).take(nNumber).mkString(", "))
 
}

Seed7[edit]

The function popcount below converts the integer into a bitset. The function card is used to compute the population count of the bitset.

$ include "seed7_05.s7i";
 
const func integer: popcount (in integer: n) is
return card(bitset(n));
 
const proc: main is func
local
var integer: count is 0;
var integer: num is 0;
begin
for num range 0 to 29 do
write(popcount(3 ** num) <& " ");
end for;
writeln;
write("evil: ");
for num range 0 to integer.last until count >= 30 do
if not odd(popcount(num)) then
write(num <& " ");
incr(count);
end if;
end for;
writeln;
write("odious: ");
count := 0;
for num range 0 to integer.last until count >= 30 do
if odd(popcount(num)) then
write(num <& " ");
incr(count);
end if;
end for;
writeln;
end func;
Output:
1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25 
evil:   0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58 
odious: 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59 

Sidef[edit]

func population_count(n) { n.as_bin.count('1') }
say "#{0..29 «**« 3 «call« population_count -> join(' ')}"
 
var numbers = 60.of { |i|
[i, population_count(i)]
}
 
say "Evil: #{numbers.grep{_[1] %% 2}.map{.first}.join(' ')}"
say "Odious: #{numbers.grep{_[1] & 1}.map{.first}.join(' ')}"
Output:
1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
Evil:   0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
Odious: 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

Swift[edit]

func populationCount(n: Int) -> Int {
guard n >= 0 else { fatalError() }
 
return String(n, radix: 2).filter({ $0 == "1" }).count
}
 
let pows = (0...)
.lazy
.map({ Int(pow(3, Double($0))) })
.map(populationCount)
.prefix(30)
 
let evils = (0...)
.lazy
.filter({ populationCount(n: $0) & 1 == 0 })
.prefix(30)
 
let odious = (0...)
.lazy
.filter({ populationCount(n: $0) & 1 == 1 })
.prefix(30)
 
print("Powers:", Array(pows))
print("Evils:", Array(evils))
print("Odious:", Array(odious))
Output:
Powers: [1, 2, 2, 4, 3, 6, 6, 5, 6, 8, 9, 13, 10, 11, 14, 15, 11, 14, 14, 17, 17, 20, 19, 22, 16, 18, 24, 30, 25, 25]
Evils: [0, 3, 5, 6, 9, 10, 12, 15, 17, 18, 20, 23, 24, 27, 29, 30, 33, 34, 36, 39, 40, 43, 45, 46, 48, 51, 53, 54, 57, 58]
Odious: [1, 2, 4, 7, 8, 11, 13, 14, 16, 19, 21, 22, 25, 26, 28, 31, 32, 35, 37, 38, 41, 42, 44, 47, 49, 50, 52, 55, 56, 59]


Symsyn[edit]

 
 
| Pop Count 3^i
 
i
if i < 30
(3^i) x
popcount x 63 x
~ x $r
+ $r $s
+ ' ' $s
+ i
goif
endif
"' Pop Count 3^i : ' $s " []
 
| Evil Numbers
 
i
cnt
if cnt < 30
popcount i 7 x
x:0:1 y
if y <> 1
+ cnt
~ i $r
+ $r $e
+ ' ' $e
endif
+ i
goif
endif
"' Evil Numbers  : ' $e " []
 
| Odious Numbers
 
i
cnt
if cnt < 30
popcount i 7 x
x:0:1 y
if y = 1
+ cnt
~ i $r
+ $r $o
+ ' ' $o
endif
+ i
goif
endif
"' Odious Numbers : ' $o " []
 
Output:
Pop Count 3^i : 1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
Evil Numbers  : 0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
Odious Numbers : 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

Tcl[edit]

Works with: Tcl version 8.6
package require Tcl 8.6
 
proc hammingWeight {n} {
tcl::mathop::+ {*}[split [format %llb $n] ""]
}
for {set n 0;set l {}} {$n<30} {incr n} {
lappend l [hammingWeight [expr {3**$n}]]
}
puts "p3: $l"
for {set n 0;set e [set o {}]} {[llength $e]<30||[llength $o]<30} {incr n} {
lappend [expr {[hammingWeight $n]&1 ? "o" : "e"}] $n
}
puts "evil: [lrange $e 0 29]"
puts "odious: [lrange $o 0 29]"
Output:
p3: 1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
evil: 0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
odious: 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

UNIX Shell[edit]

Works with: bash
popcount() {
local -i n=$1
(( n < 0 )) && return 1
local ones=0
while (( n > 0 )); do
(( ones += n%2 ))
(( n /= 2 ))
done
echo $ones
}
 
popcount_3s=()
n=1
for (( i=0; i<30; i++ )); do
popcount_3s+=( $(popcount $n) )
(( n *= 3 ))
done
echo "powers of 3 popcounts: ${popcount_3s[*]}"
 
evil=()
odious=()
n=0
while (( ${#evil[@]} < 30 || ${#odious[@]} < 30 )); do
p=$( popcount $n )
if (( $p%2 == 0 )); then
evil+=( $n )
else
odious+=( $n )
fi
(( n++ ))
done
echo "evil nums: ${evil[*]:0:30}"
echo "odious nums: ${odious[*]:0:30}"
Output:
powers of 3 popcounts: 1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
evil nums:   0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
odious nums: 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

VBA[edit]

Translation of: VBScript
Works with: VBA version VBA Excel 2013

The Decimal subtype of Variant does the job to expand 32-bit integers (Long) to 28-digit integers (Decimal).

Sub Population_count()
nmax = 30
b = 3
n = 0: List = "": bb = 1
For i = 0 To nmax - 1
List = List & " " & popcount(bb)
bb = bb * b
Next 'i
Debug.Print "popcounts of the powers of " & b
Debug.Print List
For j = 0 To 1
If j = 0 Then c = "evil numbers" Else c = "odious numbers"
n = 0: List = "": i = 0
While n < nmax
If (popcount(i) Mod 2) = j Then
n = n + 1
List = List & " " & i
End If
i = i + 1
Wend
Debug.Print c
Debug.Print List
Next 'j
End Sub 'Population_count

Private Function popcount(x)
Dim y, xx, xq, xr
xx = x
While xx > 0
xq = Int(xx / 2)
xr = xx - xq * 2
If xr = 1 Then y = y + 1
xx = xq
Wend
popcount = y
End Function 'popcount
Output:
popcounts of the powers of 3:
 1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
evil numbers:
 0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
odious numbers:
' 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

VBScript[edit]

Use of the variant currency subtype. Currency mode is a gray area where some operators do not work, for instance: ^ \ Mod

' Population count - VBScript - 10/05/2019
nmax=30
b=3
n=0: list="": bb=1
For i=0 To nmax-1
list=list & " " & popcount(bb)
bb=bb*b
Next 'i
Msgbox list,,"popcounts of the powers of " & b
For j=0 to 1
If j=0 Then c="evil numbers": Else c="odious numbers"
n=0: list="": i=0
While n<nmax
If (popcount(i) Mod 2)=j Then
n=n+1
list=list & " " & i
End If
i=i+1
Wend
Msgbox list,,c
Next 'j

Function popcount(x)
Dim y,xx,xq,xr
xx=x
While xx>0
xq=Int(xx/2)
xr=xx-xq*2
If xr=1 Then y=y+1
xx=xq
Wend
popcount=y
End Function 'popcount
Output:
popcounts of the powers of 3:
 1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
evil numbers:
 0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
odious numbers:
 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

Visual Basic .NET[edit]

Translation of: C#
Module Module1
 
Function PopCnt(ByVal n As Long) As Integer
Return Convert.ToString(n, 2).ToCharArray().Where(Function(x) x = "1").Count()
End Function
 
Sub Aline(ByVal a As List(Of Integer), ByVal title As String)
Console.WriteLine("{0, -8}{1}", title, String.Join(" ", a.Take(30)))
End Sub
 
Sub Main(ByVal args As String())
Console.WriteLine("Population Counts:")
Dim t As New List(Of Integer), e As New List(Of Integer), o As New List(Of Integer)
For count As Integer = 0 To 99
If PopCnt(count) Mod 2 = 0 Then e.Add(count) Else o.Add(count)
If count < 30 Then t.Add(PopCnt(Math.Pow(3, count)))
Next
Aline(t, "3^n :") : Aline(e, "Evil:") : Aline(o, "Odious:")
''' Extra:
Dim eo As Boolean = e.Contains(0), res As String = "", i As Integer = 0
e.Add(0) : o.Add(0)
Do
If eo Then
If e(i + 1) = e(i) + 1 Then
res += "͞ " : i += 1
ElseIf o(i) = e(i) + 1 Then
res += "↓" : eo = Not eo
Else
res += "\" : eo = Not eo : i += 1
End If
Else
If o(i + 1) = o(i) + 1 Then
res += "͢ " : i += 1
ElseIf e(i) = o(i) + 1 Then
res += "↑" : eo = Not eo
Else
res += "/" : eo = Not eo : i += 1
End If
End If
Loop Until i >= e.Count - 1
Console.WriteLine(vbLf & "Pattern:{0}", res.Substring(0, res.Count() - 1))
If System.Diagnostics.Debugger.IsAttached Then Console.ReadKey()
End Sub
End Module
 
Output:

Added a "Pattern" line. Not quite getting the arrows I wanted, but the "Pattern" line shows the sequence pattern of integers for the Evil and Odious output. The pattern goes to about 50, whereas only the first 30 Evil and Odious integers are shown.

Population Counts:
3^n :   1 2 2 4 3 6 6 5 6 8 9 13 10 11 14 15 11 14 14 17 17 20 19 22 16 18 24 30 25 25
Evil:   0 3 5 6 9 10 12 15 17 18 20 23 24 27 29 30 33 34 36 39 40 43 45 46 48 51 53 54 57 58
Odious: 1 2 4 7 8 11 13 14 16 19 21 22 25 26 28 31 32 35 37 38 41 42 44 47 49 50 52 55 56 59

Pattern:↓͢ ↑\↑͞ ↓͢ ↑͞ ↓/↓͢ ↑\↑͞ ↓/↓͢ ↑͞ ↓͢ ↑\↑͞ ↓͢ ↑͞ ↓/↓͢ ↑͞ ↓͢ ↑\↑͞ ↓/↓͢ ↑\↑͞ ↓͢ ↑͞ ↓/↓͢ ↑\↑͞ ↓/↓͢ ↑͞ ↓͢ ↑\↑͞ ↓/↓͢ ↑\↑͞ ↓͢ ↑͞ ↓/↓͢ ↑͞ ↓͢ ↑
P.S., The underscore-right-arrows and overscore characters on the Pattern line may not appear properly on some browsers.

Yabasic[edit]

print "Pop count (3^x): "
 
for i = 0 to 29
print population(3^i);
next
print "\n"
 
print "Evil: "
EvilOdious(30)
print "\n"
 
print "Odious: "
EvilOdious(30, 1)
print "\n"
 
sub EvilOdious(limit, type)
local i, count, eo
 
repeat
eo = mod(population(i), 2)
if (type and eo) or (not type and not eo) count = count + 1 : print i;
i = i + 1
until(count = limit)
end sub
 
sub population(number)
local i, binary$, popul
 
binary$ = bin$(number)
for i = 1 to len(binary$)
popul = popul + val(mid$(binary$, i, 1))
next
return popul
end sub

zkl[edit]

Ints have the 1s count as a property.

n:=1; do(30){ print(n.num1s,","); n*=3 } println();
 
println("evil: ",[0..].filter(30,fcn(n){ n.num1s.isEven }).concat(","));
 
// now, as an iterator aka lazy:
println("odious: ",(0).walker(*).tweak( // 0,1,2,3,4... iterator
fcn(n){ if(n.num1s.isEven) Void.Skip else n }).walk(30).concat(","));
Output:
1,2,2,4,3,6,6,5,6,8,9,13,10,11,14,15,11,14,14,17,17,20,19,22,16,18,24,30,25,25,
evil: 0,3,5,6,9,10,12,15,17,18,20,23,24,27,29,30,33,34,36,39,40,43,45,46,48,51,53,54,57,58
odious: 1,2,4,7,8,11,13,14,16,19,21,22,25,26,28,31,32,35,37,38,41,42,44,47,49,50,52,55,56,59