#!/usr/bin/perl
use warnings;
use strict;

my %options = (
        one => \&one,
        two => \&two,
        three => \&three,
);
my $ret; # return code from the sub
while(chomp(my $opt = <STDIN>)){
        if(exists $options{$opt}) {
                $ret = &{$options{$opt}};
                last if $ret == 0;
        }
        else { default(); }
}

sub one {
print "one\n";
return 1;
}

sub two {
print "two\n";
return 1;
}

sub three {
print "three and break the loop\n";
return 0;
}

sub default {
print "Default\n";
}