#include <stdio.h>

void swap(int x, int y){
	int temp;

        temp = x;
        x = y;
        y = temp;
}

void swap1(int* ax, int* ay){
	int temp;
	temp = *ax;
	*ax=*ay;
	*ay=temp;
}

int main(){
	int x=4, y=7;
	swap(x,y);
	printf("%d %d\n", x, y);

	swap1(&x, &y);
	printf("%d %d\n", x, y);

	return 0;
}