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)

use std::io;
fn main() {
    let mut l1 = String::new();
    let stdin = io::stdin();
    stdin.read_line(&mut l1).unwrap();
    let mut iter = l1.split_whitespace();
    let mut v1: i32 = iter.next().unwrap().parse().unwrap();
    let v2: i32 = iter.next().unwrap().parse().unwrap();
    let mut count = 0;
    loop {
        if v1 < v2 {
            break;
        }
        v1 = v1 / v2;
        count += 1;
    }
    count += 1;
    println!("{}", count);
}