#include<iostream>
#include<algorithm>
using namespace std;
using lint=int64_t;

int main()
{
	int N;

	cin >> N;

	int ans=0;
	for(int i=1;;)
	{
		if(i>=N)
			break;
		i*=2;
		ans++;
	}

	cout << ans << endl;
	return 0;
}