#include<bits/stdc++.h>
using namespace std;
int main(){
	int x,y,z;
	cin>>x>>y;
	z=y/x;
	cout<<z*5<<endl;
}
/**************************************************************
	Problem: 1417
	User: xiaojingxuan
	Language: C++
	Result: Accepted
	Time:12 ms
	Memory:2072 kb
****************************************************************/