#include <bits/stdc++.h>
using namespace std;
int p[7][7] = {
    {0, 300, 500, 600, 700, 1350, 1650},   {300, 0, 350, 450, 600, 1150, 1500},
    {500, 350, 0, 250, 400, 1000, 1350},   {600, 450, 250, 0, 250, 850, 1300},
    {700, 600, 400, 250, 0, 600, 1150},    {1350, 1150, 1000, 850, 600, 0, 500},
    {1650, 1500, 1350, 1300, 1150, 500, 0}};
int d[7][7] = {{0, 6, 13, 18, 23, 43, 58}, {6, 0, 7, 12, 17, 37, 52},
               {13, 7, 0, 5, 10, 30, 45},  {18, 12, 5, 0, 5, 25, 40},
               {23, 17, 10, 5, 0, 20, 35}, {43, 37, 30, 25, 20, 0, 15},
               {58, 52, 45, 40, 35, 15, 0}};
int main() {
  int a, b;
  while (cin >> a, a) {
    int h, m;
    bool half = false;
    cin >> h >> m;
    int s = h * 60 + m;
    if (17 * 60 + 30 <= s && s < 19 * 60 + 30) half = true;
    cin >> b;
    cin >> h >> m;
    s = h * 60 + m;
    if (17 * 60 + 30 <= s && s < 19 * 60 + 30) half = true;
    a--, b--;
    int price = p[a][b];
    int dist = d[a][b];
    if (dist <= 40 && half) price /= 2;
    cout << price + (price % 50) << endl;
  }
  return 0;
}
