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# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;

namespace atcorder
{
    class Program
    {
        public static void Main()
        {
            string[] In = Console.ReadLine().Split(' ');
            int n = int.Parse(In[0]);
            int k = int.Parse(In[1]);
            int val = 1;
            int cnt = 0;
            while (n>=val)
            {
                cnt++;
                val *= k;
            }
            Console.WriteLine(cnt);
        }
    }
}