#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
//using mint = modint1000000007;
//const int mod = 1000000007;
//using mint = modint998244353;
//const int mod = 998244353;
//const int INF = 1e9;
const long long LINF = 1e18;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i,l,r)for(int i=(l);i<(r);++i)
#define rrep(i, n) for (int i = (n) - 1; i >= 0; --i)
#define rrep2(i,l,r)for(int i=(r) - 1;i>=(l);--i)
#define all(x) (x).begin(),(x).end()
#define allR(x) (x).rbegin(),(x).rend()
#define P pair<int,int>
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }
namespace RangeAddRangeMin {
	// 区間加算・区間最小値取得
	using S = long long;
	using F = long long;
	const S INF = 8e18;
	S op(S a, S b) { return std::min(a, b); }
	S e() { return INF; }
	S mapping(F f, S x) { return f + x; }
	F composition(F f, F g) { return f + g; }
	F id() { return 0; }
	using lazy_segtree = atcoder::lazy_segtree<S, op, e, F, mapping, composition, id>;
};
namespace RangeAddRangeMax {
	// 区間加算・区間最大値取得
	using S = long long;
	using F = long long;
	const S INF = 8e18;
	S op(S a, S b) { return std::max(a, b); }
	S e() { return -INF; }
	S mapping(F f, S x) { return f + x; }
	F composition(F f, F g) { return f + g; }
	F id() { return 0; }
	using lazy_segtree = atcoder::lazy_segtree<S, op, e, F, mapping, composition, id>;
}
int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	int n; cin >> n;
	vector<long long>a(n);
	rep(i, n)cin >> a[i];
	auto segLMin = RangeAddRangeMin::lazy_segtree(vector<long long>(n));
	auto segLMax = RangeAddRangeMax::lazy_segtree(vector<long long>(n));
	vector<long long>lmin(n), lmax(n);
	rep(i, n) {
		segLMin.apply(0, i + 1, a[i]);
		segLMax.apply(0, i + 1, a[i]);
		lmin[i] = segLMin.prod(0, i + 1);
		lmax[i] = segLMax.prod(0, i + 1);
	}

	auto segRMin = RangeAddRangeMin::lazy_segtree(vector<long long>(n));
	auto segRMax = RangeAddRangeMax::lazy_segtree(vector<long long>(n));
	vector<long long>rmin(n), rmax(n);
	rrep(i, n) {
		segRMin.apply(i, n, a[i]);
		segRMax.apply(i, n, a[i]);
		rmin[i] = segRMin.prod(i, n);
		rmax[i] = segRMax.prod(i, n);
	}
	rep2(i, 1, n) {
		chmin(lmin[i], lmin[i - 1]);
		chmax(lmax[i], lmax[i - 1]);
	}
	rrep(i, n - 1) {
		chmin(rmin[i], rmin[i + 1]);
		chmax(rmax[i], rmax[i + 1]);
	}
	long long ans = -LINF;
	rep(i, n - 1) {
		chmax(ans, lmin[i] * rmin[i + 1]);
		chmax(ans, lmax[i] * rmax[i + 1]);
		//cout << lmin[i] << " " << lmax[i] << endl;
	}
	cout << ans << endl;
	return 0;
}