#define _USE_MATH_DEFINES #include using namespace std; using i32 = int; using i64 = long long int; using f64 = double; using str = string; template using vec = vector; template using heap = priority_queue, greater>; #define times(n, i) for (i32 i = 0; i < (n); ++i) #define range(a, b, i) for (i32 i = (a); i < (b); ++i) #define upto(a, b, i) for (i32 i = (a); i <= (b); ++i) #define downto(a, b, i) for (i32 i = (a); i >= (b); --i) #define all(xs) (xs).begin(), (xs).end() #define sortall(xs) sort(all(xs)) #define reverseall(xs) reverse(all(xs)) #define uniqueall(xs) (xs).erase(unique(all(xs)), (xs).end()) #define even(x) (((x) & 1) == 0) #define odd(x) (((x) & 1) == 1) #define head(xs) *(xs).begin() #define last(xs) *(xs).rbegin() #define append emplace_back #define findge lower_bound #define findgt upper_bound const i64 MOD = 1000000007; const f64 EPS = 1e-10; i64 n; i64 a[17]; i32 main() { cin >> n; times(n, i) { cin >> a[i]; } i64 maxv = a[0]; i64 minv = a[0]; i64 v[2] = { maxv, minv }; upto(1, n-1, i) { times(2, j) { maxv = max(maxv, v[j] + a[i]); maxv = max(maxv, v[j] - a[i]); maxv = max(maxv, v[j] * a[i]); if (a[i] != 0) maxv = max(maxv, v[j] / a[i]); } times(2, j) { minv = min(minv, v[j] + a[i]); minv = min(minv, v[j] - a[i]); minv = min(minv, v[j] * a[i]); if (a[i] != 0) minv = min(minv, v[j] / a[i]); } v[0] = maxv; v[1] = minv; } cout << v[0] << endl; return 0; }