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++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <bits/stdc++.h>
using namespace std;
int main() {
  int n,k;
  cin>>n>>k;
  int ans=1;
  int b=1;
  for(int i=0;i<10000;i++){
    for(int j=0;j<ans-1;j++){
      b*=k;
    }
    if(b<=n&&n<=(b*k)-1){
      cout<<ans<<endl;
      break;
    }
    b=1;
    ans++;
  }
}