/*
TASK:number
LANG:C++
*/


# include <iostream.h>

int main()
{int n;
 int k;
 int d1,d2;
 int d3;
 cin>>n;
 cin>>d1;
 cin>>d2;
 cin>>d3;
 if (n<20) {k=d2-d1;
	    cout<<k;
	    }
 if (n>20) {k=d2-d1+d3%5;
	    }
 cout<<endl;
 return 0;
}