#include <stdio.h>
#include <stdlib.h>

void swap(int *a, int *b);

int main()
{
    int a = 3, b = 4;
    swap(&a, &b);
    printf("a=%d, b=%d", a, b);
}

void swap(int *a, int *b)
{
    const int temp = *a;
    *a = *b;
    *b = temp;
}