Submission #1607556

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Source Code Expand

#include <bits/stdc++.h>

using namespace std;
/** whole range */
#define whole(xs) (xs).begin(), (xs).end()
typedef long long ll;

namespace {
    int N;
    vector<ll> A;
    void input() {
        cin >> N;
        A.resize(N);
        for (int i = 0; i < N; i++) cin >> A[i];
    }

    void solve() {
        map<ll, int> M;
        for (auto a : A) {
            M[a]++;
        }
        vector<ll> cs{0, 0};
        for (auto m : M) {
            auto key = m.first;
            auto count = m.second;
            if (count >= 4) {
                cs.push_back(key);
                cs.push_back(key);
            } else if (count >= 2) {
                cs.push_back(key);
            }
        }
        sort(whole(cs));
        reverse(whole(cs));
        cout << cs[0] * cs[1] << endl;
    }
}

int main() {
    input(); solve();
    return 0;
}

Submission Info

Judge Result