Problem:
Score : 300 points

Problem Statement

As a token of his gratitude, Takahashi has decided to give his mother an integer sequence.
The sequence A needs to satisfy the conditions below:

A consists of integers between X and Y (inclusive).

For each 1\leq i \leq |A|-1, A_{i+1} is a multiple of A_i and strictly greater than A_i.

Find the maximum possible length of the sequence.

Constraints

1 \leq X \leq Y \leq 10^{18}

All input values are integers.

Input

Input is given from Standard Input in the following format:

X Y

Output

Print the maximum possible length of the sequence.

Sample Input 1

3 20

Sample Output 1

3

The sequence 3,6,18 satisfies the conditions.

Sample Input 2

25 100

Sample Output 2

3

Sample Input 3

314159265 358979323846264338

Sample Output 3

31

Solution in Rust (1.15.1) (judge verdict: Accepted)

fn main() {
    let (x, y) = {
        let v = read_vec::<u64>();
        (v[0], v[1])
    };

    println!("{}", solve(x, y));
}

fn solve(x: u64, y: u64) -> u64 {
    let mut cnt: u64 = 1;
    let mut c = x;
    while c <= y {
        if 2 * c <= y {
            cnt += 1;
            c = 2 * c;
            continue;
        }
        break;
    }
    cnt
}

#[test]
fn test1() {
    assert_eq!(solve(3, 20), 3);
}

#[test]
fn test2() {
    assert_eq!(solve(25, 100), 3);
}

#[test]
fn test3() {
    assert_eq!(solve(314159265, 358979323846264338), 31);
}

fn read_vec<T: std::str::FromStr>() -> Vec<T> {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    s.trim().split_whitespace().map(|e| e.parse().ok().unwrap()).collect()
}