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++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define F(i, j, k) for(register ll i = j; i <= k; ++i)
#define D(i, j, k) for(register ll i = j; i >= k; --i)
#define random(x) (rand() % (x)) + 1
#define pb push_back
#define fi first
#define se second
#define pp pair<ll, ll>
#define mp make_pair
#define error(x) cerr << #x << "=" << x << endl
//***********var defination*********
const ll maxn = 2e5+5;
ll n, m, x, y, z;
ll a[maxn];
ll calc(ll x) {
    ll ret = 0;
    while(x) {
	ret += x % 10;
	x /= 10;
    }
    return ret;
}
int main() {
    cin >> n;
    z = calc(n);
    F(i, 1, 10000000) z = min(z, calc(i * n));
    cout << z << endl;
    return 0;
}