#include<bits/stdc++.h>
using namespace std;
int main(){
    int n;
    cin>>n;
    if(n<10){
        printf("%.1f",n*1.5);
    }else{
        printf("%.1f",n*1.2);
    }
} 
/**************************************************************
	Problem: 1630
	User: yangjunwen
	Language: C++
	Result: Accepted
	Time:11 ms
	Memory:2072 kb
****************************************************************/