#include <stdio.h>

void tausche(int* x, int* y) {
	int hilfe = *x;
	*x = *y;
	*y = hilfe;
}
 
int main() {
	int a=4;
	int b=7;
	printf("Vorher: a=%i b=%i \n",a,b);
	tausche(&a,&b);
	printf("Nachher: a=%i b=%i \n",a,b);
	return 0;
}