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 PHP7 (7.0.15) (judge verdict: Accepted)

<?php
//error_reporting(0);
//$N = trim(fgets(STDIN));
list($N,$K) = explode(" ",trim(fgets(STDIN)));
//$A = array_map('intval',explode(" ",trim(fgets(STDIN))));
//function chmax(&$a,$b) {if ($a<$b){$a=$b;return true;}return false;}
//function chmix(&$a,$b) {if ($a>$b){$a=$b;return true;}return false;}


printf("%d\n",strlen(base_convert($N,10,$K)));