// compile: make data
// run: ./data < data.in
#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#ifdef LOCAL
#include <debug/codeforces.h>
#define debug(x...) _debug_print(#x, x);
#define Debug(x...) _debug_print_format(#x, x);
std::ifstream terminal("/dev/tty");
#define PP cerr<<"\033[1;30mpause...\e[0m",terminal.ignore();
#else
#define debug(x...)
#define Debug(x...)
#define PP
#endif
template<typename...Args> void print_(Args...args){((cout<<args<<" "),...)<<endl;}
#define rep(i,a,b) for(int i=(a);i<(int)(b);++i)
#define sz(v) ((int)(v).size())
#define print(...) print_(__VA_ARGS__);
#define FIND(a, x) ((find(a.begin(),a.end(),(x))!=a.end())?1:0)
#define cmin(x,...) x=min({(x),__VA_ARGS__})
#define cmax(x,...) x=max({(x),__VA_ARGS__})
#define INTMAX (int)(9223372036854775807)
#define INF (int)(1152921504606846976)
#define NaN (int)(0x8b88e1d0595d51d1)
#define double long double
#define int long long
#define uint unsigned long long
#define MAXN 200010
struct stmin {
vector<int> a, lg;
vector<vector<int>> dp;
stmin(vector<int> v) {
a = v;
build();
}
void build() {
int logn = log2(sz(a)) + 2;
dp.assign(sz(a), vector<int>(logn, 0));
rep(i, 0, sz(a)) dp[i][0] = a[i];
rep(j, 1, logn) {
rep(i, 0, sz(a)) {
dp[i][j] = min(dp[i][j-1], dp[min(i + (1 << (j-1)), sz(a)-1)][j-1]);
}
}
lg.resize(sz(a)+1); lg[1] = 0;
rep(i, 2, sz(a)+1) lg[i] = lg[i/2] + 1;
}
int query(int l, int r) {
int j = lg[r - l + 1];
return min(dp[l][j], dp[r - (1 << j) + 1][j]);
}
};
int32_t main() {
ios::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);
int n; cin >> n;
vector<int> a(n);
rep(i, 0, n) cin >> a[i];
stmin st(a);
function<int(int, int)> cdq = [&](int l, int r) {
if (l == r) return a[l];
int mid = (l + r) / 2;
int lc = cdq(l, mid), rc = cdq(mid+1, r);
set<int, greater<int>> s;
rep(i, l, r+1) if (a[i] <= min(a[mid], a[mid+1])) s.insert(a[i]);
int i = mid, j = mid+1, height = min(a[mid], a[mid+1]), cur = 2 * height;
for (auto it = s.begin(); it != s.end(); ++it) {
while (i-1 >= l && a[i-1] >= *it) --i, cmin(height, a[i]);
while (j+1 <= r && a[j+1] >= *it) ++j, cmin(height, a[j]);
cmax(cur, (j - i + 1) * height);
}
return max({lc, rc, cur});
};
int ans = cdq(0, n-1);
cout << ans << endl;
return 0;
}
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