// sum_arr2.c -- sums the elements of an array
#include <stdio.h>
#define SIZE 10

int sump(int * start, int * end);

int main(void)
{
	int marbles[SIZE] = {20, 10, 5, 39, 4, 16, 19, 26, 31, 20};
	long answer;
	
	answer = sump(marbles, marbles + SIZE);
	printf("The total sum of marbles is %ld.\n", answer);
	
	return 0;
}

// uses pointer arithmetic
int sump(int * start, int * end)
{
	int total = 0;

	while (start < end)
	{
		// add value to total
		total += *start;
		// advance pointer to next element
		start++;
	}
	
	return total;
}