#include<iostream>
using namespace std;
int s[7][7]={{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}};

int main(){
  int sc,sh,sm,ec,eh,em; 
  while(cin>>sc&&sc){
    cin>>sh>>sm>>ec>>eh>>em;
    int an=s[sc-1][ec-1],S=sh*100+sm,E=eh*100+em;
    if(((1730<=S&&S<=1930)||(1730<=E&&E<=1930))&&(s[ec-1][sc-1]<=40))an/=2;
    if(an%50)an-=an%50,an+=50;
    cout<<an<<endl;
  }
  return 0;
}