#include <stdio.h>
#include <iostream>

using namespace std;

void proc1(int &x)
{
    x = 13;
}

void proc2(int &x, int &y, int &z)
{
    x = 1;
    y = 2;
    z = x + y;
}

int main()
{
    int i = 12;

    printf("Before proc1: i = %d\n", i);
    proc1(i);
    printf(" After proc1: i = %d\n", i);

    i = 12;
    proc2(i, i, i);
    printf(" After proc2: i = %d\n", i);
}