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 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<stdio.h>
#include<math.h>
int main()
{
    long long n,i,j,num=0,dn,y,x;
    scanf("%lld %lld",&n,&y);
    dn=n;
    i=1;
    for(j=n;j>0;j=j/y)
    {
        num=num+(n%y)*i;
        i=i*10;
        n=n/y;
    }

x=((log10(num))+1);
printf("%lld\n",x);

}