# Change the base representation of a non-negative integer
use strict;
sub GenerateBase
{
my $base = shift;
$base = 62 if $base > 62;
my @nums = (0..9,'a'..'z','A'..'Z')[0..$base-1];
my $index = 0;
my %nums = map {$_,$index++} @nums;
my $To = sub
{
my $number = shift;
return $nums[0] if $number == 0;
my $rep = ""; # this will be the end value.
while( $number > 0 )
{
$rep = $nums[$number % $base] . $rep;
$number = int( $number / $base );
}
return $rep;
};
my $From = sub
{
my $rep = shift;
my $number = 0;
for( split //, $rep )
{
$number *= $base;
$number += $nums{$_};
}
return $number;
};
return ( $To, $From );
}
=Example usage:
my( $ToBase62, $FromBase62 ) = GenerateBase( 62 );
my $UniqueID = $ToBase62->( $$ ) . $ToBase62->( time );
my $hex = (GenerateBase(16))[0];
print $hex->( '28' );
=cut
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, 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, 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: |
| & | | & |
| < | | < |
| > | | > |
| [ | | [ |
| ] | | ] |
Link using PerlMonks shortcuts! What shortcuts can I use for linking?
See Writeup Formatting Tips and other pages linked from there for more info.
|
|