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 C (GCC 5.4.1) (judge verdict: Accepted)

/* ex3_3
   tamayama */

#include<stdio.h>
 int main (void){
 
    int N,K;
    int input_K;
    int digit=1;
    scanf("%d %d",&N,&K);
    input_K = K;

    while(K <= N){  /*Nを超えないように何回KをK倍したかを求める*/
    K = input_K*K;  /*もとのKの値をinput_KとおいてKと区別*/
    digit++;
    }
    printf("%d\n",digit);

    return 0;
}