#include<bits/stdc++.h>
using namespace std;
int main(){
    int n,a;
    cin>>n;
    a=n*3;
    printf("%d",a);
}
/**************************************************************
	Problem: 1596
	User: toughuatao1
	Language: C++
	Result: Accepted
	Time:7 ms
	Memory:2072 kb
****************************************************************/