#pragma GCC optimize("O3")
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("avx,avx2")
#include <bits/stdc++.h>
#define INF 1000000001LL
#define LNF 1000000000000000001LL
#define MOD 1000000007LL
#define MAX 502
#define long long long
#define all(x) x.begin(),x.end()
using namespace std;

int main()
{
	ios_base::sync_with_stdio(0); 
    cin.tie(0);

    long x;
    cin >> x;

    long y = x/2;

    for(long i = max(0LL,y-100000); i < y+100000; i++)
    {
        long res = i;
        long p = i;
        while(p)
        {
            if(res == x)
            {
                cout << i << endl;
                return 0;
            }
            p/=2;
            res+=p;
        }
    }
    assert(false);
    return 0;
}