use strict;
use warnings;
use feature qw( say );

my @aa = ("A", "C", "D", "E", "F", "G", "H", "I", "K", "L", "M", "N", 
+"P", "Q", "R", "S", "T", "V", "W", "Y");

my $pair;
for my $n1 (@aa) {
   for my $n2 (@aa) {
     $pair = $n1 . $n2;    
               
   }
}

[download]
these are the 20 amino acids and i have to make 400 possible combination of two amino acid (di amino acid) like this: 
AA AC AD ...... CA CC CD CE CF CG.....YA.....YY

[download]
I TRIED TO MODIFY THE CODE but the scope of "for" loop diminishes when it ends. why it is ending there only, since i made the variable $pair as global only giving two Y's as output

In reply to Re: doubts on perl Hash by Anonymous Monk
in thread doubts on perl Hash by raulgh5

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