tut16.cpp

// #include <iostream>
// using namespace std;

// // ITs called call by refrence using refrence variable
// void swap(int *a, int *b) {
//     int temp;
//     temp = *a ;
//     *a = *b ;
//     *b = temp ;
// }
// int main()
// {
//     int x=34 , y =99 ;

//     cout<< "The value of x is: "<<x<<endl<<"The value of y is: "<<y<<endl;
//     swap(x,y);
//     cout<< "The value of x after swap is: "<<x<<endl<<"The value of y after swap is: "<<y<<endl;
// }

//  Code with harry
#include <iostream>
using namespace std;

int sum(int a, int b)
{
  int c = a + b;
  return c;
}

// This will not swap a and b
void swap(int a, int b)
{               // temp a b
  int temp = a; // 4   4  5
  a = b;        // 4   5  5
  b = temp;     // 4   5  4
}

// Call by reference using pointers
void swapPointer(int *a, int *b)
{                // temp a b
  int temp = *a; // 4   4  5
  *a = *b;       // 4   5  5
  *b = temp;     // 4   5  4
}

// Call by reference using C++ reference Variables
// int &
void swapReferenceVar(int &a, int &b)
{               // temp a b
  int temp = a; // 4   4  5
  a = b;        // 4   5  5
  b = temp;     // 4   5  4
  // return a;
}

int main()
{
  int x = 4, y = 5;
  // cout<<"The sum of 4 and 5 is "<<sum(a, b);
  cout << "The value of x is " << x << " and the value of y is " << y << endl;
  // swap(x, y); // This will not swap a and b
  // swapPointer(&x, &y); //This will swap a and b using pointer reference
  swapReferenceVar(x, y); // This will swap a and b using reference variables
  // swapReferenceVar(x, y) = 766; //This will swap a and b using reference variables
  cout << "The value of x is " << x << " and the value of y is " << y << endl;
  return 0;
}