#include <bits/stdc++.h>

using namespace std;

using ll = long long;
using ul = unsigned long;
using ull = unsigned long long;

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

	int a, b;
	cin >> a >> b;
	int ct = a * 3600 + b * 60;

	int res;
	if (ct % (12 * 3600) == 0)
		res = 0;
	else
	{
		int dt = 12 * 3600 / 11;

		int n = ct * 11 / (12 * 3600);

		if (ct % dt)
			++n;

		res = n * 12 * 3600 / 11 - ct;
	}
	cout << res << "\n";

	return 0;
}