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;
using System.Linq;

public class Digits
{
    public static void Main(string[] args)
    {
        var vals = Console.ReadLine().Trim().Split(' ').Select(x => int.Parse(x)).ToArray();
        var num = vals[0];
        var cnt = 0;
        while (num != 0)
        {
            var result = Math.Floor((double)(num / vals[1]));
            cnt++;
            num = (int)result;
        }
        Console.WriteLine(cnt);
    }
}