#include <stdio.h>

int main()
{
    extern int sum(int *a, int n);
    int a[10] = { 1, 2, 3, 1, 2, 3, 1, 2, 3, 99 };
    printf("%d\n", sum(a, 10));
    return 0;
}


int sum(int *a, int n)
{
    if (n == 0)
	return 0;
    else
	return *a + sum(a + 1, n - 1);
}