I have a script that uses "rand" to add one of the four letters (ATCG) to a string: 

#!/bin/perl

use warnings;
use strict;

my $i =0;
my $x;
my $aa = "";

for ($i;$i<5007;$i++){
    $x = int(rand(4));
    if ($x == 0) {
        $aa .= 'A';
    }
    elsif ($ x== 1) {
        $aa .= 'T';
    }
    elsif ($x == 2) {
        $aa .= 'C';
    }
    else {
        $aa .= 'G';
    }
}
open (FILE, '>./test');
print FILE "$aa";
close (FILE);

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It works but also sends : "Useless use of private variable in void context at 8 line 24." What does it mean?

In reply to Useless use of private variable in void context at by Anonymous Monk

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