poj 2551 Ones

Ones

Time Limit: 1000MS		Memory Limit: 65536K
Total Submissions: 8948		Accepted: 5061

Description

Given any integer 0 <= n <= 10000 not divisible by 2 or 5, some multiple of n is a number which in decimal notation is a sequence of 1's. How many digits are in the smallest such a multiple of n?

Input

Each line contains a number n.

Output

Output the number of digits.

Sample Input

3 
7 
9901

Sample Output

3
6
12

#include<iostream>
using namespace std;
int main()
{
    int n, a, b;
    while (EOF != scanf("%d", &n))
    {
        a = 1;
        b = 1;
        while (a)
        {
            a = (a * 10 + 1) % n;
            b++;
        }
        printf("%d\n", b);
    }
}