use strict;
use warnings;

my ($inp, $name, $address, %directory);

print "Welcome to your own Personal Address Book!\n";

while (1) {
    while (1) {
        print "
What would you like to do?\n
ADD     Add An Entry
DEL     Delete An Entry
PRN     Print All Entries
END     End Program\n\n";

        $inp = uc getInput('');

        last if $inp eq 'ADD' || $inp eq 'DEL' ||
                $inp eq 'PRN';
        exit if $inp eq 'END';
    }
    print "\n";

    if ($inp eq 'ADD') {
        $name = getInput('Enter a name to add');
        $address = getInput('Enter the corresponding address');
        $directory{$name} = $address;
    }
    elsif ($inp eq 'DEL') {
        $name = getInput('Enter a name to remove');
        delete $directory{$name};
    }
    else {
        print "These are the people in your address book:\n\n";
        print "$_\t\t$directory{$_}\n"
            for sort keys %directory;
    }
}

sub getInput {
    my $inp;
    while (1) {
        print "$_[0]: ";
        chomp($inp = <STDIN>);
        return $inp if $inp;
    }
}