Problem:
Score : 700 points

Problem Statement

Find the smallest possible sum of the digits in the decimal notation of a positive multiple of K.

Constraints

2 \leq K \leq 10^5

K is an integer.

Input

Input is given from Standard Input in the following format:

K

Output

Print the smallest possible sum of the digits in the decimal notation of a positive multiple of K.

Sample Input 1

6

Sample Output 1

3

12=6×2 yields the smallest sum.

Sample Input 2

41

Sample Output 2

5

11111=41×271 yields the smallest sum.

Sample Input 3

79992

Sample Output 3

36

Solution in C (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <stdio.h>
int main(void){
    int k;
    scanf("%d",&k);
    while(k%2==0)k/=2;
    while(k%5==0)k/=5;
    int po=1;
    int ans=1;
    if(k!=1)while(1){
        po*=10;
        po+=1;
        po%=k;
        ans++;
        if(po==0)break;
    }
    printf("%d",ans);
    return 0;
}