c++

#include <bits/stdc++.h>
using namespace std;

int main() {
	long long s, u, a, b, c, d, e ;
	cin >> s >> u;
	a = ceil (s / u) + 10;
	b = floor (a / 60);
	c = a - (b * 60);
	d = 7 - b;
	e = 60 - c;
	cout << d << ":" << e << endl;
	return 0;
}