#include <bits/stdc++.h>
using namespace std;
int main(){
   int x,y,a;
   cin>>x>>y;
   a=5*(y/x);
   cout<<a;
}

/**************************************************************
	Problem: 1417
	User: huangluowei
	Language: C++
	Result: Accepted
	Time:13 ms
	Memory:2072 kb
****************************************************************/