is there a fast way to tell all the numbers that a spesific number divides on without leftovers (like for the spesific number "20" it divedes on 1,2,4,5,10,20 and stays as an integer) ? How to find those "1,2,4,5,10,20" in the fastest way ?

that's my code :

#!/usr/bin/perl
use Math::BigInt;

print "Enter the big number : ";
$x = readline(*STDIN);
print "Enter the little number : ";
$y = readline(*STDIN);
$z = $x - $y;
$i = $z;
@all = '';
$j = 0;
system cls;

($sec,$min,$hour,$mday,$mon,$year,$wday,$yday) = gmtime(time);

while ($i ne 0) {
$t = $z / $i;
$k = Math::BigInt->new($t);
$k = $k->is_int();
if ($k eq "1") {$j++; $all[$j] = "$t\n";}
$i--; print "$i\n";
}
($sec1,$min1,$hour1,$mday,$mon,$year,$wday,$yday) = gmtime(time);

$data="Dis.txt";
open(DAT, $data) || die("Could not open file!");
@al=<DAT>;
@al = @all;
open(DAT,">$data") || die("Cannot Open File");
print DAT @al; 
close(DAT);

print "@all It took ", $min1 - $min, " minuts!\n";
$w = readline(*STDIN);

[download]

now how to make it find those numbers FASTER ?

20040705 Edit by castaway: Changed title from 'Didision'

In reply to Finding all divisors of an integer by chiburashka

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.