#include <iostream>
#include <cstdio>
#include <cmath>
#include <ctime>
#include <cstdlib>
#include <cassert>
#include <vector>
#include <list>
#include <stack>
#include <queue>
#include <deque>
#include <map>
#include <set>
#include <bitset>
#include <string>
#include <algorithm>
#include <utility>
#define llint long long
#define inf 1e18
#define rep(x, s, t) for(llint (x) = (s); (x) < (t); (x)++)
#define Rep(x, s, t) for(llint (x) = (s); (x) <= (t); (x)++)
#define chmin(x, y) (x) = min((x), (y))
#define chmax(x, y) (x) = max((x), (y))
#define X(h, m, s) (h*3600+m*60+s*60/11)

using namespace std;
typedef pair<llint, llint> P;

llint a, b;
llint t[] = {
	X(0, 0, 0), X(1, 5, 5), X(2, 10, 10), X(3, 16, 4),
	X(4, 21, 9), X(5, 27, 1), X(6, 32, 8), X(7, 38, 2),
	X(8, 43, 7), X(9, 49, 1), X(10, 54, 6)
};

int main(void)
{
	ios::sync_with_stdio(0);
	cin.tie(0);
	
	cin >> a >> b;
	llint s = a*3600+b*60;
	s %= (12*3600);
	
	llint ans = 0;
	while(1){
		for(int i = 0; i < 11; i++){
			if(s == t[i]) goto end;
		}
		ans++;
		s = (s+1)%(12*3600);
	}
	end:;
	cout << ans << endl;
	
	return 0;
}