/*
 * Extremely simple (and silly) example of defining and using function.
 */
#include <stdio.h>

int add(int a, int b);

int main(void) {

	int x, y;
	printf("enter x, y\n");
	if (scanf("%d %d", &x, &y) != 2) {
		printf("not number\n");
		return 1;
	}
	printf("%d + %d is %d\n", x, y, add(x, y));

	return 0;
}

int add(int a, int b) {
	return a+b;
}