Advanced features of C++ functions

There are 3 advanced features of C++ functions as compared to C. They are Call by Reference, Function Overloading and Default Arguments. You can read more about them here.

A simple program showing all the three features as follows:

//Program tested on Microsoft Visual Studio 2008 - Zahid Ghadialy
//Example of pointer to const and const pointer
#include<iostream>

using namespace std;

//Call by reference
void swap(int& a, int &b)
{
  int temp = a;
  a = b;
  b = temp;
}

//Overloaded function: Call by reference (pointers)
void swap(int *a, int *b)
{
  int temp = *a;
  *a = *b;
  *b = temp;
}

//Pass by value with Default arguments
void doSwap(int a, int b = 1)
{
  swap(a,b);
  cout<<"After Local Swap: a = "<< a <<" b = "<< b <<endl;
}

int main()
{
  int a = 10, b = 17;
  cout<<"Before Swap : a = "<< a <<" b = "<< b <<endl;
  swap(a, b);
  cout<<"After Swap 1: a = "<< a <<" b = "<< b <<endl;
  swap(&a, &b);
  cout<<"After Swap 2: a = "<< a <<" b = "<< b <<endl;
  doSwap(a, b);
  doSwap(a);
  cout<<"After DoSwap: a = "<< a <<" b = "<< b <<endl;

  return 0;
}

The output is as follows: