#include<bits/stdc++.h>
#define int long long
using namespace std;
const int N=2e5+15;


signed main(){
	int a,b,c,d;cin>>a>>b>>c>>d;
	b-=22;
	if(a==5){
		if(b==5)cout<<(24-c-1)*60+(60-d)+23*60+24*60;
        else if(b==6)cout<<(24-c-1)*60+(60-d)+23*60;
		else if(c<=2&&d<=59)cout<<(24-c-1)*60+(60-d)-60;
		else cout<<(24-c-1)*60+(60-d);
	}
	else{
		if(b==a)cout<<(24-c-1)*60+(60-d)+24*60;
		else cout<<(24-c-1)*60+(60-d);
	}
	return 0;
}