#include "bits/stdc++.h"

using namespace std;

using ll = long long;
using ld = long double;
using P = pair<int, int>;
constexpr ld EPS = 1e-12;
constexpr int INF = numeric_limits<int>::max() / 2;
constexpr int MOD = 1e9 + 7;

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

    ll n;
    cin >> n;
    ll b = 1;
    int res = 0;
    while (b * 2 <= n)
    {
        b *= 2;
        res++;
    }
    if (b == n)
        cout << res << endl;
    else
        cout << res + 1 << endl;
}