#include <bits/stdc++.h>
using namespace std;
int main() {
  long p[8][8] = {
      {0, 300, 500, 600, 700, 1350, 1650}, {6, 0, 350, 450, 600, 1150, 1500},
      {13, 7, 0, 250, 400, 1000, 1350},    {18, 12, 5, 0, 250, 850, 1300},
      {23, 17, 10, 5, 0, 600, 1150},       {43, 37, 30, 25, 20, 0, 500},
      {58, 52, 45, 40, 35, 15, 0}};
  long s, e, hs, ms, he, me, a, b, c;
  while (cin >> s) {
    if (s == 0) break;
    cin >> hs >> ms >> e >> he >> me;
    if (s > e) {
      a = s;
      s = e;
      e = a;
    }
    hs *= 60;
    hs += ms;
    he *= 60;
    he += me;
    a = (hs - 1050) * (he - 1050);
    b = (hs - 1170) * (he - 1170);
    if (a <= 0) {
      if (b > 0)
        c = 1;
      else
        c = 0;
    } else {
      if (b <= 0)
        c = 1;
      else
        c = 0;
    }
    if (p[e - 1][s - 1] <= 40 && c == 1)
      cout << ((p[s - 1][e - 1] / 50 + 1) / 2) * 50 << endl;
    else
      cout << p[s - 1][e - 1] << endl;
  }
  return 0;
}
