1 Write a simple program to validate passing by value and passing by reference. 2 Initialize a variable and display its value. 3 Pass the variable by value to a function. Change the value of the variable in the pass by value function. Display the modified value inside the function. 4 After the pass by value function returned, display the value again in the main function. 5 Pass the same variable, now passing by reference to another function. Change the value of the variable in the pass by reference function. Display the modified value inside the function.