# 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
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