reference function in c 2b 2b

1// function definition to swap the values.
2void swap(int &x, int &y) {
3   int temp;
4   temp = x; /* save the value at address x */
5   x = y;    /* put y into x */
6   y = temp; /* put x into y */
7  
8   return;
9}

1#include <iostream>
2using namespace std;
3
4// function declaration
5void swap(int &x, int &y);
6
7int main () {
8   // local variable declaration:
9   int a = 100;
10   int b = 200;
11 
12   cout << "Before swap, value of a :" << a << endl;
13   cout << "Before swap, value of b :" << b << endl;
14
15   /* calling a function to swap the values using variable reference.*/
16   swap(a, b);
17
18   cout << "After swap, value of a :" << a << endl;
19   cout << "After swap, value of b :" << b << endl;
20 
21   return 0;
22}