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 <functional>
#include <map>
#include <math.h>

using namespace std;

int main()
{
    long long n, t;
    int k;
    int count = 0;
    cin>>n>>k;
    if(n>2){
        for(int i = 0;t<n;i++) {
            t=pow(k,i);
            count++;
        }
        if(pow(k,count-1) == n){
            cout<<count;
        }
        else{
            cout<<count-1;
        }
    }

    else if(n==2){
        cout<<"2";
    }
    else{
        cout<<"1";
    }
}