#include "bits/stdc++.h" #define ALL(a) (a).begin(),(a).end() #define SORT(c) sort((c).begin(),(c).end()) #define DESCSORT(c) sort(c.begin(), c.end(), greater()) using namespace std; using LL = long long int; using LD = long double; using pii = pair; using pll = pair; using pdd = pair; using vi = vector; using vvi = vector; using vvvi = vector; using vl = vector; using vvl = vector; using vvvl = vector; using vd = vector; using vvd = vector; using vs = vector; using vb = vector; using vvb = vector; const int INF = (1 << 30) - 1; const LL INF64 = ((LL)1 << 62) - 1; const double PI = 3.1415926535897932384626433832795; const int dy[] = { 0, 1, 0, -1 }; const int dx[] = { 1, 0, -1, 0 }; int gcd(int x, int y) { return y ? gcd(y, x % y) : x; } LL gcd(LL x, LL y) { return y ? gcd(y, x % y) : x; } int main() { ios::sync_with_stdio(false); cin.tie(0); int n; cin >> n; vi a(n); for (int i = 0; i < n; i++) { cin >> a[i]; } vector dp(n); dp[0].first = a[0]; dp[0].second = a[0]; for (int i = 1; i < n; i++) { LL v; if (a[i] != 0) { v = max(dp[i - 1].first / a[i], dp[i - 1].second / a[i]); dp[i].first = v; v = min(dp[i - 1].first / a[i], dp[i - 1].second / a[i]); dp[i].second = v; } v = max(dp[i - 1].first * a[i], dp[i - 1].second * a[i]); dp[i].first = max(dp[i].first, v); v = min(dp[i - 1].first * a[i], dp[i - 1].second * a[i]); dp[i].second = min(dp[i].second, v); v = max(dp[i - 1].first + a[i], dp[i - 1].second + a[i]); dp[i].first = max(dp[i].first, v); v = min(dp[i - 1].first + a[i], dp[i - 1].second + a[i]); dp[i].second = min(dp[i].second, v); v = max(dp[i - 1].first - a[i], dp[i - 1].second - a[i]); dp[i].first = max(dp[i].first, v); v = min(dp[i - 1].first - a[i], dp[i - 1].second - a[i]); dp[i].second = min(dp[i].second, v); } cout << dp[n - 1].first << endl; return 0; }