Or this: 

use warnings;
use strict;

my @p = qw[PA5098  PA5100  PA5092  PA3175];

for my $i ( 0 .. $#p ) {
    last if $i == $#p;
    for my $j ( 0 .. $#p ) {
        print join( " " => ( $p[$i], $p[$j], $j - $i ) ), $/ unless $i
+ >= $j;
    }
}

[download]
Output 
PA5098 PA5100 1
PA5098 PA5092 2
PA5098 PA3175 3
PA5100 PA5092 1
PA5100 PA3175 2
PA5092 PA3175 1

[download]
I kind of like AnomalousMonk solution, because it has no help from ifs and unless. McA solution is also cool for me, but I don't like C-for loop in perl! :)

If you tell me, I'll forget.
If you show me, I'll remember.
if you involve me, I'll understand.
--- Author unknown to me

In reply to Re: problem with loop by 2teez
in thread problem with loop by Anonymous Monk

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