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

int main() {
    int N;
    cin >> N;
    int n = N;
    int ans = 0;
    int fans = 0;
    if(N%2 == 0) {
        while (N) {
            N /= 2;
            ans++;
        }
        N = n;
        N /= 2;
        N--;
        fans = 1+N;
        cout << max(ans,fans) << endl;
    }
    else {
        while (N) {
            N /= 2;
            ans++;
        }
        N = n;
        N /= 2;
        fans = 1+N;
        cout << max(ans,fans) << endl;
    }
}