Loops/While

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Revision as of 14:43, 21 June 2008 by Lupus (talk | contribs) (added Fortran)
Task
Loops/While
You are encouraged to solve this task according to the task description, using any language you may know.

Start an integer value at 1024. Loop while it is greater than 0. Print the value (with a newline) and divide it by two each time through the loop.

Ada

<ada> declare

  I : Integer := 1024;

begin

  while I > 0 loop
     Put_Line(Integer'Image(I));
     I := I / 2;
  end loop;

end; </ada>

BASIC

Works with: QuickBasic version 4.5

<qbasic>i = 1024 while i > 0

  print i
  i = i / 2

wend</qbasic>

C

<c>int i = 1024; while(i > 0) {

 printf("%d\n", i);
 i /= 2;

}</c>

D

<D>import std.stdio;

int i = 1024; void main() {

   while(i > 0) {
       writefln("%s", i);
       i >>= 1;
   }

}</d>

Forth

: halving ( n -- )
  begin  dup 0 >
  while  cr dup .  2/
  repeat drop ;
1024 halving

Fortran

Works with: Fortran version 90 and later
INTEGER :: i = 1024
DO WHILE (i > 0)
  WRITE(*,*) i
  i = i / 2
END DO

Java

<java>int i = 1024; while(i > 0){

  System.out.println(i);
  i >>= 1; //also acceptable: i /= 2;

}</java>

JavaScript

<javascript>var n = 1024; while (n>0) {

print(n);
n/=2;

}</javascript>

make "n 1024
while [:n > 0] [print :n  make "n :n / 2]

MAXScript

a = 1024
while a > 0 do
(
    print a
    a /= 2
)

OCaml

<ocaml>let n = ref 1024;; while !n > 0 do

 Printf.printf "%d\n" !n;
 n := !n / 2

done;;</ocaml>

Pascal

<pascal> program divby2(output);

var

 i: integer;

begin

 i := 1024;
 while i > 0 do
   begin
     writeln(i);
     i := i div 2
   end

end. </pascal>

Perl

<perl>$n = 1024; while ($n > 0) {

   print "$n\n";
   $n >>= 1; # also acceptable: use integer; $n /= 2;

}</perl>

Pop11

lvars i = 1024;
while i > 0 do
    printf(i, '%p\n');
    i div 2 -> i;
endwhile;

Python

<python>n = 1024 while n > 0:

   print n
   n = n / 2</python>

UnixPipes

(echo 1024>p.res;tail -f p.res) | while read a ; do
   test $a -gt 0 && (expr $a / 2  >> p.res ; echo $a) || exit 0
done


V

1024 [0 >] [
   dup puts
   2 / >int
] while