#! /usr/bin/perl 
use strict;

my %son_father;
my $choice;
my $name1;
my $add_dad;

%son_father = (Jeff => "Doug",
               Thomas => "Evan",
               Robert => "Jason",
               Bruce => "Richard",
               Clark => "Jon")  ;
               
my $menu = <<MENU;

         SON_FATHER Hash Operations

a- Add a son-father pair
d- Delete a son-father pair
e- exit the program
g- Get a father
o- Output the hash neatly
r- Replace a father
x- get a grand father
MENU

while (1) {
  # display the menu
  print $menu, "\n\n";

  # get the user choice 
  print "Make your choice: ";
  chomp($choice = lc <STDIN>);

  # fulfill the user request 
  if ($choice eq 'a'){
    print "Enter a male name: ";
    chomp ($name1 = lc <STDIN>);
      } if (exists $son_father{$name1}) {
          print "Duplicate name -- try again!\n";
          } else {
              print "Add a father: ";
              chomp ($add_dad = lc <STDIN>);
              $son_father{$name1} = {$add_dad}; 
  } 

  if ($choice eq 'd') {
    print "Enter a male name: ";
    chomp ($name1 = lc <STDIN>);
      } if (exists $son_father{$name1}) {
          delete $son_father{$name1};
          } else {
             print "Sorry, couldn't find you -- try again later!";
  } 

   if ($choice eq 'e') {
   print "Come back again -- goodbye!";
   exit;  
  } 

   else {
   print "Invalid choice, TRY AGAIN!\n";
  }
}