#include<iostream>
using namespace std;

int cost[8][8] = 
{
{},
{0,0,300,500,600,700,1350,1650},
{0,6,0,350,450,600,1150,1500},
{0,13,7,0,250,400,1000,1350},
{0,18,12,5,0,250,850,1300},
{0,23,17,10,5,0,600,1150},
{0,43,37,30,25,20,0,500},
{0,58,52,45,40,35,15,0}
};

int l,lh,lm,a,ah,am;

int main(){
	while(true){
		cin >> l;
		if(!l)
			return 0;
		cin >> lh >> lm;
		lm+=lh*100;
		cin >> a;
		cin >> ah >> am;
		am+=ah*100;
		if(cost[max(l,a)][min(l,a)] > 40)
			cout << cost[min(l,a)][max(l,a)] << endl;
		else if((lm>=1730&&lm<=1930)||(am>=1730&&am<=1930)){
			bool flag = false;
			if((cost[min(l,a)][max(l,a)]/2)%50)
				flag = true;
			int ans = cost[min(l,a)][max(l,a)]/2-((cost[min(l,a)][max(l,a)]/2)%50);
			if(flag)
				ans+=50;
			cout << ans << endl;
		}else
			cout << cost[min(l,a)][max(l,a)] << endl;
	}
}