#pragma GCC target("avx2")
#pragma GCC optimize("03")
#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h>
using namespace std; typedef long double ld; typedef long long ll;
typedef unsigned long long ull;
#define endl "\n"
#define FOR(i,a,b) for(int i=(a);i<=(b);i++)
#define rep(i,n) for(int i=0;i<(n);i++)
#define PII pair<int, int>
#define PLL pair<ll, ll>
#define ALL(x) (x).begin(), (x).end()
constexpr int INF=1<<30; constexpr ll LINF=1LL<<60; constexpr ll mod=1e9+7; constexpr int NIL = -1;
template<class T>inline bool chmax(T &a, const T &b) { if (a<b) { a = b; return 1; } return 0; }
template<class T>inline bool chmin(T &a, const T &b) { if (b<a) { a = b; return 1; } return 0; }
template<class T>inline int popcount(T a) {return __builtin_popcount(a);}
template<class T>inline T emod(T a, T p) { return (a%p + p) % p;}
//-------------------
int a[20];
int n;

ll dfs(ll cur, int idx) {
    ll mx = 0;
    if(idx==n) return cur;
    chmax(mx, dfs(cur + a[idx], idx+1));
    chmax(mx, dfs(cur - a[idx], idx+1));
    chmax(mx, dfs(cur * a[idx], idx+1));
    return mx;
}

int main() {
    cin.tie(0); ios::sync_with_stdio(false); cout << fixed << setprecision(15);
    cin >> n;
    rep(i, n) {
        cin >> a[i];
    }
    cout << dfs(0, 0) << endl;
    return 0;
}