Fix the maximum (bad initial value)

Challenge

The starter initialises the running max to 0, which is wrong for all-negative arrays. Fix int find_max(const int *a, int n) (n >= 1) to return the true maximum.

Starter code

int find_max(const int *a, int n) {
    int m = 0;  /* BUG: wrong for all-negative arrays */
    for (int i = 0; i < n; i++)
        if (a[i] > m) m = a[i];
    return m;
}