#include<bits/stdc++.h>
using namespace std;
int main(){
    int n,s;
    cin>>n;
	s=n*3;
	cout<<s; 
}
/**************************************************************
	Problem: 1596
	User: xuezihong1
	Language: C++
	Result: Accepted
	Time:10 ms
	Memory:2072 kb
****************************************************************/