#include<bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define ll long long
#define ull unsigned long long
#define pii pair<int, int>
#define pll pair<ll, ll>
#define pli pair<ll, int>
#define debug(x) cout << #x << " = " << x << '\n'
#define all(a) a.begin(), a.end()
#define SZ(a) (int)(a).size()
const int N = 5e5 + 5;
const int mod = 1e9 + 7;
const ll inf64 = 3e18;
const int inf32 = 2e9 + 5;
int n, a[N], q;
pii que[N];
namespace sub1 {
int mx[105][105];
void sol() {
for(int i = 1; i <= n; i++) {
mx[i][i] = a[i];
for(int j = i + 1; j <= n; j++)
mx[i][j] = max(mx[i][j - 1], a[j]);
}
for(int t = 1; t <= q; t++) {
int l, r;
tie(l, r) = que[t];
int ans = 0;
for(int i = l; i <= r; i++) {
for(int j = i + 1; j <= r; j++) {
int k = j + (j - i);
if(k <= r) ans = max(ans, a[i] + a[j] + mx[k][r]);
}
}
cout << ans << '\n';
}
}
}
namespace sub2 {
void sol() {
vector<vector<int>> mx(n + 3, vector<int>(n + 3, 0));
for(int i = 1; i <= n; i++) {
mx[i][i] = a[i];
for(int j = i + 1; j <= n; j++)
mx[i][j] = max(mx[i][j - 1], a[j]);
}
vector<vector<int>> dp(n + 3, vector<int>(n + 3, 0));
for(int i = n; i >= 1; i--) for(int j = i + 2; j <= n; j++) {
if(j == i + 2) {
dp[i][j] = a[i] + a[i + 1] + a[i + 2];
continue;
}
dp[i][j] = max(dp[i][j - 1], dp[i + 1][j]);
dp[i][j] = max(dp[i][j], a[i] + a[j] + mx[i + 1][(i + j) / 2]);
}
for(int i = 1; i <= q; i++)
cout << dp[que[i].fi][que[i].se] << '\n';
}
}
struct SegmentTree {
int n;
vector<int> node, lz, vals;
SegmentTree() {}
SegmentTree(int n) : n(n), node(n << 2, 0), lz(n << 2, 0), vals(n << 2, 0) {}
void build(int id, int l, int r) {
if(l == r) {
vals[id] = a[l];
return;
}
int mid = (l + r) >> 1;
build(id << 1, l, mid);
build(id << 1 | 1, mid + 1, r);
vals[id] = max(vals[id << 1], vals[id << 1 | 1]);
}
void down(int id) {
if(!lz[id]) return;
int v = lz[id];
lz[id << 1] = max(lz[id << 1], v);
lz[id << 1 | 1] = max(lz[id << 1 | 1], v);
node[id << 1] = max(node[id << 1], v + vals[id << 1]);
node[id << 1 | 1] = max(node[id << 1 | 1], v + vals[id << 1 | 1]);
lz[id] = 0;
}
void upd(int id, int l, int r, int x, int y, int v) {
if(x <= l && r <= y) {
lz[id] = max(lz[id], v);
node[id] = max(node[id], vals[id] + v);
return;
}
down(id);
int mid = (l + r) >> 1;
if(mid >= x) upd(id << 1, l, mid, x, y, v);
if(mid + 1 <= y) upd(id << 1 | 1, mid + 1, r, x, y, v);
node[id] = max(node[id << 1], node[id << 1 | 1]);
}
void upd(int l, int r, int x) { if(l <= r) upd(1, 1, n, l, r, x); }
int get(int id, int l, int r, int x, int y) {
if(x <= l && r <= y) return node[id];
down(id);
int mid = (l + r) >> 1;
if(mid < x) return get(id << 1 | 1, mid + 1, r, x, y);
if(mid + 1 > y) return get(id << 1, l, mid, x, y);
return max(get(id << 1, l, mid, x, y), get(id << 1 | 1, mid + 1, r, x, y));
}
int get(int l, int r) { return (l <= r ? get(1, 1, n, l, r) : 0); }
};
namespace sub4 {
vector<pii> qr[N];
int ans[N];
void sol() {
for(int i = 1; i <= q; i++)
qr[que[i].fi].push_back(make_pair(que[i].se, i));
SegmentTree seg(n);
seg.build(1, 1, n);
stack<int> st;
for(int i = n; i >= 1; i--) {
while(SZ(st) && a[st.top()] <= a[i]) {
int x = i, y = st.top(); st.pop();
seg.upd(y + (y - x), n, a[x] + a[y]);
}
if(SZ(st)) {
int x = i, y = st.top();
seg.upd(y + (y - x), n, a[x] + a[y]);
}
st.push(i);
for(pii Q : qr[i]) {
int r, idx;
tie(r, idx) = Q;
ans[idx] = seg.get(i, r);
}
}
for(int i = 1; i <= q; i++)
cout << ans[i] << '\n';
}
}
void solve() {
cin >> n;
for(int i = 1; i <= n; i++)
cin >> a[i];
cin >> q;
for(int i = 1; i <= q; i++)
cin >> que[i].fi >> que[i].se;
if(n <= 100 && q <= 100) return sub1::sol();
if(n <= 5000) return sub2::sol();
return sub4::sol();
}
int main() {
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
int test = 1;
// cin >> test;
while(test--) solve();
}
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