#include <stdio.h>

// Error: con i < n, el ciclo nunca mira al propio n.
int count_multiples(int n, int step) {
    int count = 0;
    for (int i = 1; i < n; i++) {
        if (i % step == 0) {
            count = count + 1;
        }
    }
    return count;
}

int main(void) {
    printf("%d\n", count_multiples(9, 3));
    printf("%d\n", count_multiples(10, 3));
    return 0;
}