/**
 Author : Kamonasish Roy (Bullet)
 Time : 2025-02-25 13:03:09
 **/

#include<bits/stdc++.h>
using namespace std;
const long long M=5e5,MOD=1e9+7;
typedef long long ll;

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    int t=1;
    //cin>>t;
    while(t--){
    	int n;
    	cin>>n;
    	assert(n> 0 && n<101);
    	int answer=n;
    	while(n>1){
    		answer+=(n/2);
    		n=n/2+(n & 1);
    	}
    	cout<<answer<<"\n";
    	
    	
    	}
    	
    	   
    return 0;
 
}