#include<bits/stdc++.h>
using namespace std;
int main(){
    int n;
    float h,a,b;
    cin>>n;
    a=n%10;
    b=n/10;
    h=b/a;
    printf("%.1f",h);
     
}
 
/**************************************************************
	Problem: 1607
	User: xuezihong1
	Language: C++
	Result: Accepted
	Time:14 ms
	Memory:2072 kb
****************************************************************/