// NO FUNCIONA
#include <stdio.h>

void swap(int a, int b) {
	int aux;

	printf("a=%d, b=%d\n", a, b);
	aux = a;
	a = b;
	b = aux;
	printf("a=%d, b=%d\n", a, b);
}

main() {
	int a=2, b=3;

	printf("a=%d, b=%d\n", a, b);
	swap(a,b);
	printf("a=%d, b=%d UPS!\n", a, b);
}