#include <bits/stdc++.h>

using namespace std;

#define FOR(i,a,b) for(int i=(a);i<(b);i++)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(),(v).end()

template<typename A, typename B> inline bool chmax(A &a, B b) { if (a<b) { a=b; return 1; } return 0; }
template<typename A, typename B> inline bool chmin(A &a, B b) { if (a>b) { a=b; return 1; } return 0; }

typedef unsigned long long ull;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const ll INF = 1ll<<29;
const ll MOD = 1000000007;
const double EPS  = 1e-10;

ll dp[2][16];
int n;
ll a[16];

int main() {
	cin >> n;
	REP(i, n) scanf("%lld", a + i);
	
	fill(dp[0], dp[1], -INF);
	fill(dp[1], dp[2], INF);
	
	dp[0][0] = dp[1][0] = a[0];
	
	FOR(i, 1, n) {
		REP(j, 2) {
			REP(k, 4) {
				ll now = dp[j][i - 1];
				
				if (k == 3 && a[i] == 0) continue;
				
				switch (k) {
					case 0: now += a[i]; break;
					case 1: now -= a[i]; break;
					case 2: now *= a[i]; break;
					case 3: now /= a[i]; break;
				}
				
				chmax(dp[0][i], now);
				chmin(dp[1][i], now);
			}
		}
	}
	
	cout << dp[0][n - 1] << endl;
	
	return 0;
}