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 Java8 (OpenJDK 1.8.0) (judge verdict: Wrong Answer)

import java.util.*;

public class Main
{
	public static void main(String args[])
	{
		Scanner s1=new Scanner (System.in);
		double n,r,count;
		n=s1.nextDouble();
		r=s1.nextDouble();
		double m = (Math.log(n)/Math.log(r));
		count=(int)(Math.floor(m)+1);
		System.out.println(count);
	}
}