#include<bits/stdc++.h>
using namespace std;
int main(){

	int n,x;
	//const float pi=3.14;
	cin>>n;
	x=n*3;
	cout<<x; 
	return 0;
}


/**************************************************************
	Problem: 1596
	User: tangkaixuan
	Language: C++
	Result: Accepted
	Time:7 ms
	Memory:2072 kb
****************************************************************/