#include<bits/stdc++.h>
using namespace std;
int main()
{
	int n;
	cin>>n;
	cout<<n*3;
	
	
	
	


	return 0;
}

/**************************************************************
	Problem: 1596
	User: 21A
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2072 kb
****************************************************************/