/*
 * compute sum of integers entered as input (any number of them), using
 * a loop
 */
#include <stdio.h>

long sum(void) {
	long n;
	long sum = 0;
	/* arguably a little obscure but very C-idiomatic */
	while (scanf("%ld", &n) == 1) {
		sum += n;
	}
	return sum;
}

int main(void) {
	printf("enter integers to sum, anything else to stop\n");
	printf("sum %ld\n", sum());
	return 0;
}