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>
#include <iostream>
#include <vector>
#include <string>
#include <math.h>
using namespace std;
typedef long long ll;
const double EPS = 1e-9;
typedef vector<int> vint;
typedef pair<int, int> pint;
#define inf 1e+9
#define rep(i, n) REP(i, 0, n)
#define all(v) v.begin(), v.end()
#define msg(a) cout << #a << " " << a << endl;
#define REP(i, x, n) for(int i = x; i < n; i++)
#define pri(a) cout << a << endl;

int main(){
  cin.tie(nullptr);
	ios::sync_with_stdio(false);

  ll n,k,ans=0;
  cin >> n >> k;

  if(n>=1){
    ans++;
  }

  int i=1,h=k;
  while(n>=h){
    ans++;
    i++;
    h = pow(k,i);
  }


  pri(ans);

}