import java.io.PrintWriter;
import java.util.*;

public class Main {

    Scanner sc = new Scanner(System.in);

    PrintWriter out = new PrintWriter(System.out);

    public static void main(String[] args) {
        new Main().run();
    }

    void run() {

        long x = sc.nextLong()*1000;
        long y = sc.nextLong()*1000;
        long h = sc.nextLong();

        int ans = 0;

        label:
        while (x>h || y>h) {
            if (y<x) {
                long tmp = y;
                y = x;
                x = tmp;
            }
            if (x>h) {
                x /= 2;
                h *= 2;
                ans++;
                continue label;
            }
            if (y>h) {
                y /= 2;
                h *= 2;
                ans++;
            }
        }

        out.print(ans);
        out.flush();

    }

}