#include <bits/stdc++.h>
using namespace std;

int main()
{
	long long p;
	cin >> p;

	long long m = (1LL << p) - 1;
	long long ans = 0;
	while( m > 0 ) {
		ans += m % 2;
		m /= 2;
	}

	cout << ans << endl;
}