Question

In C Not C++
write a function that takes in the reference of an int array and return the value -1 if sum is odd, and 1 if the sum is even.

Answer 1

#include <stdio.h>

int sum_even_odd(int *arr, int size);

int main() {
    int arr1[] = {4, 9, 1, 2};
    int arr2[] = {4, 9, 1, 2, 3};
    printf("%d\n", sum_even_odd(arr1, 4));
    printf("%d\n", sum_even_odd(arr2, 5));
    return 0;
}

int sum_even_odd(int *arr, int size) {
    int sum = 0, i;
    for (i = 0; i < size; ++i) {
        sum += arr[i];
    }
    if (sum % 2 == 0)
        return 1;
    else
        return -1;
}