#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <map>
using namespace std;

int main() {
    int n,ans = 0;
    cin >> n;
    while(n != 1){
        int a = n%2;
        n /= 2;
        n += a;
        ans++;
    }
    cout << ans << endl;
    return 0;
}