I think you want something like this:
use strict;
use warnings;

my($a) = <STDIN>;
chomp($a);
if ($a !~ /^\d+$/) {
    print "Sorry - you didn't give me a number.\n";
    exit 1;
} else {
    print "Yay!  That's a number!\n";
}

[download]
Hope that helps,
Shendal

In reply to Re: Minor querry!! by Shendal
in thread Minor querry!! by vnpandey

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