#include <bits/stdc++.h>
using namespace std;
int main(){
    int n,r;
    cin>>n;
    r=n*3;
    printf("%d",r);
    }
/**************************************************************
	Problem: 1596
	User: huanglingkai
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2072 kb
****************************************************************/