call by reference c 2b 2b example

1//call by reference example c++
2#include <iostream>
3
4using namespace std;
5
6void swap(int& x, int& y) {
7	cout << x << " " << y << endl;
8	int temp = x;
9	x = y;
10	y = temp;
11	cout << x << " " << y << endl;
12
13}
14
15int main() {
16    
17	int a = 7;
18	int b = 9;
19
20	swap(a, b);
21
22}
23

1void fun3(int a)
2{
3    a = 10;
4}
5
6int main()
7{
8    int b = 1;
9    fun3(b);
10    // b  is still 1 now!
11    return 0;   
12}