import java.io.BufferedReader;
import java.io.InputStreamReader;

public class Main {
	public static void main(String[] args) throws Exception {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		String[] sa = br.readLine().split(" ");
		long x = Long.parseLong(sa[0]) * 1000;
		long y = Long.parseLong(sa[1]) * 1000;
		long h = Long.parseLong(sa[2]);
		br.close();

		long a = Math.min(x, y);
		long b = Math.max(x, y);
		long ans = 0;
		while (a > h) {
			a /= 2;
			h *= 2;
			ans++;
		}
		while (b > h) {
			b /= 2;
			h *= 2;
			ans++;
		}
		System.out.println(ans);
	}
}