So you don't want to sort the array, you want to find the max value in it. So write a subroutine to find the max value in your array and call that (just like chromatic suggested!)

use strict; # ALWAYS!!!!!!

# MaxElementInArray( @array )
sub MaxElementInArray
{
    my $max = shift;
    my $next;
    $max = $next > $max ? $next : $max while $next = shift;
    return $max;
}

# MaxElementInArrayRef( \@array )
sub MaxElementInArrayRef
{
    my $array_ref = shift; 
    my $index = $#$array_ref; 
    my $max = $$array_ref[$index];
    $max = $$array_ref[$index] > $max ?
           $$array_ref[$index] : $max while --$index >= $[;
    return $max;
}
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Update: While examining your code in response to your statement below, I've noticed quite a few style issues: You don't use strict, you are not using CGI.pm, and you are not using subroutines to improve the readability (and maintainability) of your code. I strongly suggest you look into these things. As for your issue of trying to use a number before you have calculated it... this reveals a failure to plan before coding. Now I suspect you will need to re-write much of this code just to get things in a causal order.