Product of decimal digits of n
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- Task
Find the product of the decimal digits of a positive integer n, where n <= 100
Phix
with javascript_semantics function pdd(integer n) return sprintf("%2d",product(sq_sub(sprint(n),'0'))) end function printf(1,"Product of the decimal digits of 1..100:\n%s\n", {join_by(apply(tagset(100),pdd),1,10)})
- Output:
Product of the decimal digits of 1..100: 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 2 4 6 8 10 12 14 16 18 0 3 6 9 12 15 18 21 24 27 0 4 8 12 16 20 24 28 32 36 0 5 10 15 20 25 30 35 40 45 0 6 12 18 24 30 36 42 48 54 0 7 14 21 28 35 42 49 56 63 0 8 16 24 32 40 48 56 64 72 0 9 18 27 36 45 54 63 72 81 0
REXX
<lang rexx>/*REXX pgm finds positive integers when shown in hex that can't be written with dec digs*/ parse arg n cols . /*obtain optional argument from the CL.*/ if n== | n=="," then n = 100 /*Not specified? Then use the default.*/ if cols== | cols=="," then cols= 10 /* " " " " " " */ w= 10 /*width of a number in any column. */
title= ' the product of the decimal digits of N, where N < ' n
say ' index │'center(title, 1 + cols*(w+1) ) /*display the title for the output. */ say '───────┼'center("" , 1 + cols*(w+1), '─') /* " a sep " " " */ $=; idx= 1 /*list of products (so far); IDX=index.*/
do #=1 for n; L= length(#) /*find products of the dec. digs of J. */
p= left(#, 1) /*use first digit as the product so far*/
do j=2 for L-1 until p==0 /*add an optimization when product is 0*/
p= p * substr(#, j, 1) /*multiply the product by the next dig.*/
end /*j*/
$= $ right(p, w) /*add the product ───► the $ list. */
if #//cols \== 0 then iterate /*have we populated a line of output? */
say center(idx, 7)'│' substr($, 2); $= /*display what we have so far (cols). */
idx= idx + cols /*bump the index count for the output*/
end /*#*/ /*stick a fork in it, we're all done. */
if $\== then say center(idx, 7)"│" substr($, 2) /*possible display residual output.*/ say '───────┴'center("" , 1 + cols*(w+1), '─') /*display the foot sep for output. */</lang>
- output when using the default inputs:
index │ the product of the decimal digits of N, where N < 100 ───────┼─────────────────────────────────────────────────────────────────────────────────────────────────────────────── 1 │ 1 2 3 4 5 6 7 8 9 0 11 │ 1 2 3 4 5 6 7 8 9 0 21 │ 2 4 6 8 10 12 14 16 18 0 31 │ 3 6 9 12 15 18 21 24 27 0 41 │ 4 8 12 16 20 24 28 32 36 0 51 │ 5 10 15 20 25 30 35 40 45 0 61 │ 6 12 18 24 30 36 42 48 54 0 71 │ 7 14 21 28 35 42 49 56 63 0 81 │ 8 16 24 32 40 48 56 64 72 0 91 │ 9 18 27 36 45 54 63 72 81 0 ───────┴───────────────────────────────────────────────────────────────────────────────────────────────────────────────
Ring
<lang ring> load "stdlib.ring" see "working..." + nl see "Product of decimal digits of n:" + nl
row = 0 limit = 100
for n = 1 to limit
prod = 1
strn = string(n)
for m = 1 to len(strn)
prod = prod * number(strn[m])
next
see "" + prod + " "
row = row + 1
if row%5 = 0
see nl
ok
next
see "done..." + nl </lang>
- Output:
working... Product of decimal digits of n: 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 2 4 6 8 10 12 14 16 18 0 3 6 9 12 15 18 21 24 27 0 4 8 12 16 20 24 28 32 36 0 5 10 15 20 25 30 35 40 45 0 6 12 18 24 30 36 42 48 54 0 7 14 21 28 35 42 49 56 63 0 8 16 24 32 40 48 56 64 72 0 9 18 27 36 45 54 63 72 81 0 done...