#include <bits/stdc++.h>

using namespace std;


int main()
{
    int n, k = 0,  s = 0;
    cin >> n;
    vector<int> a;
    vector<int> res;
    while(n >= 2){
        a.push_back(n % 2);
        n/=2;
    }
    if(n)
        a.push_back(n);

    for(int i = 0; i < a.size(); ++i){
        res.push_back(pow(2, i));
    }
    reverse(res.begin(), res.end());
    for(int i = 0; i < a.size(); ++i){
        if(a[i])
            s+=res[i];
    }
    cout << s;
    return 0;
}