#include <bits/stdc++.h>
using namespace std;

int main() {
    int N;
    cin >> N;
    vector<long long> A(N);
    for (int i = 0; i < N; i++) cin >> A[i];

    if (N == 1) {
        cout << A[0] << endl;
    } else if (N % 2 == 1) {
        cout << 1 << endl;
    } else {
        sort(A.begin(), A.end());
        cout << A[0] * A[1] << endl;
    }
}