#include <bits/stdc++.h>

using namespace std;

long largestValue(vector <int> A) {
    vector<int> ps;
    /*for(int i = 0; i < A.size()-1; i++){
        int v1 = A[i];
        for(int j = i+1 j < A.size(); j++){
            int v2 = A[j];
            ps.push_back(v1*v2);            
        }
    }*/
    return 0;
    // Return the largest value of any of A's nonempty subarrays.
}

int main() {
    int n;
    cin >> n;
    vector<int> A(n);
    for(int A_i = 0; A_i < n; A_i++){
       cin >> A[A_i];
    }
    long result = largestValue(A);
    cout << result << endl;
    return 0;
}