#include <bits/stdc++.h>
#pragma warning(disable : 4996)
using namespace std;
using ld = long double;
const ld eps = 1e-9;
vector<vector<int>> money{
    {0, 300, 500, 600, 700, 1350, 1650},
    {0, 0, 350, 450, 600, 1150, 1500},
    {0, 0, 0, 250, 400, 1000, 1350},
    {0, 0, 0, 0, 250, 850, 1300},
    {0, 0, 0, 0, 0, 600, 1150},
    {0, 0, 0, 0, 0, 0, 500},
    {0, 0, 0, 0, 0, 0, 0},
};
vector<int> dis{6, 7, 5, 5, 20, 15};
int main() {
  while (1) {
    int d;
    cin >> d;
    int start, goal;
    {
      int h, m;
      cin >> h >> m;
      start = h * 60 + m;
    }
    int a;
    cin >> a;
    {
      int h, m;
      cin >> h >> m;
      goal = h * 60 + m;
    }
    d--;
    a--;
    if (d < a) swap(d, a);
    int cost = money[a][d];
    cost /= 50;
    int distance = 0;
    for (int i = a; i < d; ++i) {
      distance += dis[i];
    }
    bool flag = false;
    if ((start <= 1170 || 1050 <= goal) && !(start < 1050 && 1170 < goal))
      flag = true;
    if (distance <= 40 && flag) cost = (cost + 1) / 2;
    cost *= 50;
    cout << cost << endl;
  }
  return 0;
}
