#!/usr/local/bin/perl -wT
#use strict; #Make sure that all variables are declared before being executed. 

#Create an array:
   @myArray = ("Jen Chen", "Robinson Hood", "Donald Duck", "Mickey Mouse");
   print "The elements in the array \@myArray are: @myArray\n";

$lastIndex = 0;
$lastIndex = @myArray; #This will return the last index in the array.
$lastIndex += 1;
   print "The number of elements in the array \@myArray are: $lastIndex\n";
$lastIndex--; #Now $lastIndex has value of 3.

#Now loop thru each element of the array:
$count=0;
   print "\nLooping thru all elements in the \@myArray:\n";
while($count <= $lastIndex){
   print "$myArray[$count]\t";
   $count++;
   if($count > $lastIndex){
     print "\n";
   }
}

#To add elements into an existing array, we first find the last index of the 
#array then add the next index element to the array as follow:

  $myArray[($lastIndex + 1)] = "Jimmy the Great";
  $myArray[($lastIndex + 2)] = "Joanne the Great";

$newLastIndex = $#myArray;
$count=0;
   print "\nLooping thru all elements in the \@myArray:\n";

while($count < $newLastIndex){
   print "$myArray[$count]\t";
   $count++;
   if($count == $newLastIndex){
     print "\n";
   }
}

#Another way to add elements to an existing array is the use of the function
# push(Array_name, new_value) as follow: (Note that the new elements are added
#to the RIGHT end of the array. To add elements to the left of an array we use
#the function unshift(Array_Name, value,...) and shift(Array_Name)).
   push(@myArray, "Sleeping Beauty");
   push(@myArray, "Aladdin", "Walt Disney", "The Golden Fish");

   print "\nLooping thru all elements in the \@myArray:\n";

foreach $thing (@myArray){
     print "$thing\t";
}
   print "\n";

#Conversely if we want to remove the elements form an array (from the right end
#element) we would use the function pop(Array_name) as follow:
   $strTmp = pop(@myArray);
   print "The element removed from the array is: $strTmp\n";

#Since we use quite a bit of the function shift() and unshift(), then we try
#out some of them here:
   unshift(@myArray, "1", "2");

   print "\nLooping thru all elements in the \@myArray: after adding 1 and 2 to the \nleft of the array\n";

foreach $thing (@myArray){
     print "$thing\t";
}
     print "\n";

#This is a hash array.
%hashArray = ("one",1,"two",2);

   print "\$hashArray{one} = $hashArray{one}\n";
   print "\$hashArray{two} = $hashArray{two}\n";