Ma đạo solution FRACTION - Số chữ số thập phân :D

//Hoang Son WIBU lolicon codeforces rate 1642 khong cay
#include <bits/stdc++.h>
#define F first
#define S second
#define times double stime = clock();
#define gettime cerr << "\nTime executed: " << (clock() - stime) / CLOCKS_PER_SEC * 1000 << "ms.\n";
using namespace std;
typedef long long ll;
typedef double dou;
typedef pair<ll, int> pii;
typedef vector<int> vi;
typedef vector<vi> vvi;
const ll mod = 1000000009;

ll n;
ll powi(ll ax, ll bx){
    if(bx == 0) return 1;
    if(bx == 1) return ax;
    ll cx = powi(ax, bx/2);
    cx = cx*cx;
    if(bx%2) cx *= ax;
    return cx; 
}
int numo(ll ax, ll bx){
    int l = 0, r = 9, ans = 9;
    while(l<=r){
        int mid = (l+r)/2;
        if(ax*powi(10ll, mid) >= bx){
            r = mid - 1;
            ans = mid;
        } else l = mid + 1;
    }
    return ans;
}
map<int, bool> mp;
void process(){
    cin >> n;
    int ans = 0;
    ll kd = 1;
    while(kd%n){
        if(ans > 100000){
            ans = -1;
            break;
        }
        if(kd < n){
            int j = numo(kd, n);
            ans += j;
            kd = kd*powi(10ll, j);
        }
        if(mp[kd] == true){
            ans = -1;
            break;
        }
        mp[kd] = true;
        kd %= n;
    }
    if(ans == -1){
        cout << "NO";
    } else {
        cout << ans;
    }
}

int online = 2;
int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    if (online == 0) {
        freopen("in.inp", "r", stdin);
        freopen("out.out", "w", stdout);
    } else if (online == 1) {
        freopen(".inp", "r", stdin);
        freopen(".out", "w", stdout);
    }
    // times
    process();
    // gettime
    return 0;
}