#include <bits/stdc++.h>
using namespace std;
int main() {
  int aa[8][8] = {{0, 1, 2, 3, 4, 5, 6, 7},
                  {1, 0, 300, 500, 600, 700, 1350, 1650},
                  {2, 300, 0, 350, 450, 600, 1150, 1500},
                  {3, 500, 350, 0, 250, 400, 1000, 1350},
                  {4, 600, 450, 250, 0, 250, 850, 1300},
                  {5, 700, 600, 400, 250, 0, 600, 1150},
                  {6, 1350, 1150, 1000, 850, 600, 0, 500},
                  {7, 1650, 1500, 1350, 1300, 1150, 500, 0}};
  int bb[8][8] = {
      {0, 1, 2, 3, 4, 5, 6, 7},       {1, 0, 6, 13, 18, 23, 43, 58},
      {2, 6, 0, 7, 12, 17, 37, 52},   {3, 13, 7, 0, 5, 10, 30, 45},
      {4, 18, 12, 5, 0, 5, 25, 40},   {5, 23, 17, 10, 5, 0, 20, 35},
      {6, 43, 37, 30, 25, 20, 0, 15}, {7, 58, 52, 45, 40, 35, 15, 0}};
  int i, j, n, time00, time01, time10, time11, n2, disc, mo;
  int disc2;
  while (1) {
    disc2 = 0;
    disc = 0;
    cin >> n;
    if (n == 0) break;
    cin >> time00 >> time01;
    cin >> n2;
    cin >> time10 >> time11;
    if (time10 == 19 && time11 <= 30) {
      disc2 = 1;
    } else if (time10 == 18)
      disc2 = 1;
    else if (time10 == 17 && time11 >= 30)
      disc2 = 1;
    if (bb[n2][n] <= 40 && disc2 == 1) disc = 1;
    mo = aa[n][n2];
    if (disc == 1) {
      mo = mo / 2;
      disc = 0;
      disc2 = 0;
      if (mo % 50 != 0) mo = (mo - (mo % 50)) + 50;
    }
    cout << mo << endl;
  }
  return 0;
}
