652A - Gabriel and Caterpillar - CodeForces Solution

#include <iostream>

using namespace std;

int main() {
    int apple_height, track_height;
    cin >> track_height >> apple_height;

    int a, b;
    cin >> a >> b;

    apple_height -= track_height + 8 * a;
    a = (a - b) * 12;

    int days_to_wait = 0;
    if (apple_height <= 0) {
        days_to_wait = 0;
    }
    else if (a <= 0) {
        days_to_wait = -1;
    }
    else {
        days_to_wait = (apple_height + a - 1) / a;
    }

    cout << days_to_wait;

    return 0;
}