#include<bits/stdc++.h>
using namespace std;
int main(){
    int x,y,a,t;
    cin>>x>>y;
    a=y/x;
    t=a*5;
    cout<<t;
}
/**************************************************************
	Problem: 1417
	User: huanglingkai
	Language: C++
	Result: Accepted
	Time:9 ms
	Memory:2072 kb
****************************************************************/