bdfz_2024_summer/day12/U466180/U466180.cpp

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

using namespace std;

const int MAX_N = 1000;
const int MAX_A = 1e9;


vector<int> sieve(int limit) {
    vector<bool> is_prime(limit + 1, true);
    vector<int> primes;
    is_prime[0] = is_prime[1] = false;
    for (int i = 2; i <= limit; ++i) {
        if (is_prime[i]) {
            primes.push_back(i);
            for (int j = i * 2; j <= limit; j += i) {
                is_prime[j] = false;
            }
        }
    }
    return primes;
}

int main() {
    int n;
    cin >> n;
    vector<int> a(n);
    for (int i = 0; i < n; ++i) {
        cin >> a[i];
    }

    int sqrt_max_a = sqrt(MAX_A);
    vector<int> primes = sieve(sqrt_max_a);

    int max_sum = 0;


    for (int p : primes) {
        int current_sum = 0;
        for (int i = 0; i < n; ++i) {
            if (a[i] % p == 0) {
                current_sum += a[i];
            }
        }
        max_sum = max(max_sum, current_sum);
    }

    cout << max_sum << endl;

    return 0;
}