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.Collections.Generic;
using System.Linq;

public class Hello
{
    public static void Main()
    {
        hoge();
        System.Console.ReadLine();
    }

    public static void hoge()
    {
        var line = System.Console.ReadLine().Split(' ').Select(x=>int.Parse(x)).ToArray();
        var n = line[0];
        var k = line[1];

        List<int> lst = new List<int>();

        while(n > 0)
        {
            lst.Add(n % k);
            n /= k;
        }
        System.Console.WriteLine(lst.Count);
    }

}