Kertoma

#include <iostream>
#include <vector>
#include <cmath>

using namespace std;

typedef unsigned long long ll;

vector<ll> f(1001, 0);

void fact(ll x) {
    f[0] = 1;
    if (f[x] == 0) {
        ll start = x;
        while (f[start] == 0) {
            start--;
        }
        for (ll i = start + 1; i <= x; i++) {
            f[i] = f[i - 1] * i;
        }
    }
}

ll len(ll num) {
    ll cnt = 0;
    //cout << num << ' ';
    while (num > 0) {
        num /= 10;
        cnt++;
    }
    //cout << cnt << '\n';
    return cnt;
}

int main() {
    vector<ll> cnt(10);
    ll dig = 0;
    for (int i = 0; i < 10; i++) {
        cin >> cnt[i];
        dig += cnt[i];
    }
    ll L = 1;
    ll R = 80;
    while (R - L > 1) {
        ll M = (L + R) / 2;
        //cout << L << ' ' << R << '\n';
        fact(M);
        if (len(f[M]) < dig) {
            L = M;
        } else {
            R = M;
        }
    }
    cout << R;
}

Test 1

Group: 1, 2, 3

Verdict: ACCEPTED

Test 2

Group: 1, 2, 3

Verdict: WRONG ANSWER

Test 3

Group: 1, 2, 3

Verdict: ACCEPTED

Test 4

Group: 1, 2, 3

Verdict: ACCEPTED

Test 5

Group: 1, 2, 3

Verdict: WRONG ANSWER

Test 6

Group: 1, 2, 3

Verdict: WRONG ANSWER

Test 7

Group: 2, 3

Verdict: WRONG ANSWER

Test 8

Group: 2, 3

Verdict: WRONG ANSWER

Test 9

Group: 2, 3

Verdict: WRONG ANSWER

Test 10

Group: 2, 3

Verdict: WRONG ANSWER

Test 11

Group: 3

Verdict: WRONG ANSWER

Test 12

Group: 3

Verdict: WRONG ANSWER

Test 13

Group: 3

Verdict: WRONG ANSWER

Test 14

Group: 3

Verdict: WRONG ANSWER

Test 15

Group: 3

Verdict: WRONG ANSWER

Test 16

Group: 3

Verdict: WRONG ANSWER