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<cstdio>
#define Re register long long
long long n,K;
int main(){
	scanf("%lld%lld",&n,&K);
	if(!n){puts("1");return 0;}
	for(Re i=1,j=1;i<=31;++i){
		if(j>n){
			printf("%lld\n",i-1);
			return 0;
		}
		j*=K;
	}
}