#! /usr/bin/perl
use feature ':5.10';
use strict;
use warnings;

#define a hash
my %p = ("1","Rekjavik");

#check it's there (returns "Rekjavik")
say $p{1};

#ask for input from user (user inputs the number 1)
my $t = <>;

#the hash has disappeared! (returns undef)
say $p{$t};