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

void sum_array(int array[], int len, int* sum) {
    int* p = array;
    *sum = 0;

    while(len--) {
        *sum += *p;
        p++;
    }
}

int main() {
    int array[] = {2, 2, 2, 2, 2};
    int len = 5, sum;

    sum_array(array, len, &sum);

    printf("sum: %d", sum);

    return 0;
}