swap values

swap with pointers

#include <stdio.h>
#include <string.h>

void swap(int *, int *);
main() {
    int px, py;
    px = 1;
    py = 2;
    printf("%d %d\n", px, py);
    swap(&px, &py);
    printf("%d %d\n", px, py);
}

void swap(int *px, int *py) {
    int temp;
    
    temp = *px;
    *px = *py;
    *py = temp;
}