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 <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <string.h>
#include <math.h>
#include <string>
using namespace std;

int main() {
	cin.tie(0);
  ios::sync_with_stdio(false);
 
	int n,k,i,j,r;
  vector<int> v;
  cin>>n>>k;
  
  i=1;
  while(1){
    if(pow(k,i-1) <= n && n < pow(k,i))
      break;
    i++;
  }
  cout<<i;


  return 0;
}