#include <iostream>
using namespace std;
int main()
{
	int x,y;
	cin >> x >> y;
	cout << y/x*5;
	
	
 } 
/**************************************************************
	Problem: 1417
	User: xiaomingze
	Language: C++
	Result: Accepted
	Time:12 ms
	Memory:2072 kb
****************************************************************/