#include <iostream>

constexpr int T = 60 * 60 * 12;

void solve() {
    int a, b;
    std::cin >> a >> b;

    int t = a * 3600 + b * 60;
    int h = t % T, m = t * 12 % T;

    if (m > h) m -= T;

    int ans = 0;
    while (m <= h) {
        m += 12;
        h += 1;
        ++ans;
    }
    std::cout << ans - 1 << "\n";
}

int main() {
    std::cin.tie(nullptr);
    std::ios::sync_with_stdio(false);

    solve();

    return 0;
}