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
   Sagzar1993  */


#include <stdio.h>

int main(void) {
    //表す整数と基数を定義
    int num, numBase;

    //入力を受け取る
    scanf("%d %d", &num, &numBase);

    //桁数
    int digit = 0;

    //整数を基数で割っていき、桁数を１足していく
    while(num >= 1){
        num = num / numBase;
        digit++;
    }

    //結果を出力
    printf("%d\n", digit);
    
    return 0;
}