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

struct Pair { 
	int x, y;
};

struct Pair *new_pair() {
	struct Pair *tmp_point = malloc( sizeof( struct Pair ) );

	(*tmp_point).x = 91;
	(*tmp_point).y = 42;

	return tmp_point;
}

int main() {
	struct Pair *ptr = new_pair();

	printf( "(%d, %d)\n", (*ptr).x, (*ptr).y );

	(*ptr).y = -42;

	printf( "(%d, %d)\n", (*ptr).x, (*ptr).y );

	free( ptr );
	ptr = NULL;

	return 0;
}