#ifdef NACHIA
#define _GLIBCXX_DEBUG
#else
#define NDEBUG
#endif
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <map>
using i64 = long long;
using u64 = unsigned long long;
#define rep(i,n) for(i64 i=0; i<i64(n); i++)
const i64 INF = 1001001001001001001;
template<typename A> void chmin(A& l, const A& r){ if(r < l) l = r; }
template<typename A> void chmax(A& l, const A& r){ if(l < r) l = r; }
using namespace std;


void testcase(){
    i64 N; cin >> N;
    vector<i64> A(N); rep(i,N) cin >> A[i];
    vector<i64> S(N+1); rep(i,N) S[i+1] = S[i] + A[i];
    vector<i64> LL(N+1,INF), LX(N+1,-INF); {
        i64 l = 0, m = 0;
        for(i64 i=1; i<=N; i++){
            LL[i] = min(LL[i-1], S[i] - m);
            LX[i] = max(LX[i-1], S[i] - l);
            chmin(l, S[i]); chmax(m, S[i]);
        }
    }
    reverse(A.begin(), A.end());
    rep(i,N) S[i+1] = S[i] + A[i];
    vector<i64> RL(N+1,INF), RX(N+1,-INF); {
        i64 l = 0, m = 0;
        for(i64 i=1; i<=N; i++){
            RL[i] = min(RL[i-1], S[i] - m);
            RX[i] = max(RX[i-1], S[i] - l);
            chmin(l, S[i]); chmax(m, S[i]);
        }
    }
    i64 ans = -INF;
    for(i64 i=1; i<=N-1; i++) chmax(ans, LL[i] * RL[N-i]);
    for(i64 i=1; i<=N-1; i++) chmax(ans, LL[i] * RX[N-i]);
    for(i64 i=1; i<=N-1; i++) chmax(ans, LX[i] * RL[N-i]);
    for(i64 i=1; i<=N-1; i++) chmax(ans, LX[i] * RX[N-i]);
    cout << ans << "\n";
}

int main(){
    ios::sync_with_stdio(false); cin.tie(nullptr);
    testcase();
    return 0;
}