Problem:
Score : 200 points

Problem Statement

Given is an integer N. Find the number of digits that N has in base K.

Notes

For information on base-K representation, see Positional notation - Wikipedia.

Constraints

All values in input are integers.

1 \leq N \leq 10^9

2 \leq K \leq 10

Input

Input is given from Standard Input in the following format:

N K

Output

Print the number of digits that N has in base K.

Sample Input 1

11 2

Sample Output 1

4

In binary, 11 is represented as 1011.

Sample Input 2

1010101 10

Sample Output 2

7

Sample Input 3

314159265 3

Sample Output 3

18

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

fn main() {
    let (n, k) = {
        let s = {
            let mut s = String::new();
            std::io::stdin().read_line(&mut s).unwrap();
            s.trim_right().to_owned()
        };
        let mut integers = s.split_whitespace();
        let p: i32 = integers.next().unwrap().parse().unwrap();
        let q: i32 = integers.next().unwrap().parse().unwrap();
        (p, q)
    };
    
    let mut answer = 1;
    let mut x = k;
    while n >= x {
        x*=k;
        answer += 1;
    }

    println!("{}", answer);
}