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 Common Lisp (SBCL 2.0.3) (judge verdict: Accepted)

(defun d (n k acc)
  (if (= n 0)
      (1- acc)
      (d (- n (mod n (expt k acc))) k (1+ acc))))

(let ((n (read))
      (k (read)))
  (format t "~A~%" (d n k 1)))