#pragma GCC target("avx2") #pragma GCC optimize("03") #pragma GCC optimize("unroll-loops") #include 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 #define PLL pair #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; templateinline bool chmax(T &a, const T &b) { if (ainline bool chmin(T &a, const T &b) { if (binline int popcount(T a) {return __builtin_popcount(a);} templateinline T emod(T a, T p) { return (a%p + p) % p;} //------------------- int a[20]; int n; ll bfs() { ll mx = 0; queue q; q.push({0, 0}); while(!q.empty()) { auto [k, v] = q.front(); q.pop(); if(k == n) chmax(mx, v); else { q.push({k+1, v+a[k]}); q.push({k+1, v-a[k]}); q.push({k+1, v*a[k]}); } } return mx; } ll dp[20][2]; int main() { cin.tie(0); ios::sync_with_stdio(false); cout << fixed << setprecision(15); cin >> n; rep(i, n) { cin >> a[i]; } rep(i, 20) dp[i][0] = LINF; rep(i, 20) dp[i][1] = -LINF; dp[0][0] = a[0]; dp[0][1] = a[0]; FOR(i,1,n-1) { rep(j, 2) { chmin(dp[i][0], dp[i-1][j] + a[i]); chmin(dp[i][0], dp[i-1][j] - a[i]); chmin(dp[i][0], dp[i-1][j] * a[i]); if(a[i]!=0) chmin(dp[i][0], dp[i-1][j] / a[i]); } rep(j, 2) { chmax(dp[i][1], dp[i-1][j] + a[i]); chmax(dp[i][1], dp[i-1][j] - a[i]); chmax(dp[i][1], dp[i-1][j] * a[i]); if(a[i]!=0) chmax(dp[i][1], dp[i-1][j] / a[i]); } } cout << dp[n-1][1] << endl; return 0; }