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#include <cstdio>
#include <cstring>
#include <algorithm>
#include <iostream>
using namespace std;
const int N = 10010;
int a[N];
struct Node {
int l, r;
int sum, tmax, lmax, rmax;
} tr[N << 2];
void calc(Node &u, Node &l, Node &r) {
u.sum = l.sum + r.sum; // 区间和
u.tmax = max({l.tmax, r.tmax, l.rmax + r.lmax}); // 子区间最大值
u.lmax = max(l.lmax, l.sum + r.lmax); // 左前缀最大值
u.rmax = max(r.rmax, r.sum + l.rmax); // 右后缀最大值
}
void pushup(int u) {
calc(tr[u], tr[u << 1], tr[u << 1 | 1]);
}
void build(int u, int l, int r) {
tr[u] = {l, r, 0, 0, 0, 0};
if (l == r) {
tr[u].sum = tr[u].tmax = tr[u].lmax = tr[u].rmax = a[l];
return;
}
int mid = (tr[u].l + tr[u].r) >> 1;
build(u << 1, l, mid), build(u << 1 | 1, mid + 1, r);
pushup(u);
}
Node query(int u, int l, int r) {
if (l > tr[u].r || r < tr[u].l) return {}; // 递归出口不在我管辖范围内的情况返回0
if (l <= tr[u].l && tr[u].r <= r) return tr[u];
int mid = (tr[u].l + tr[u].r) >> 1;
if (r <= mid) return query(u << 1, l, r);
if (l > mid) return query(u << 1 | 1, l, r);
Node a = query(u << 1, l, r), b = query(u << 1 | 1, l, r), c;
calc(c, a, b);
return c;
}
int main() {
// 加快读入
ios::sync_with_stdio(false), cin.tie(0);
int T, n, m;
cin >> T;
while (T--) {
cin >> n;
for (int i = 1; i <= n; i++) cin >> a[i];
build(1, 1, n);
cin >> m;
while (m--) {
int x1, y1, x2, y2, res;
Node a, b, c;
cin >> x1 >> y1 >> x2 >> y2;
if (y1 < x2) { // 这里不能取等 不然边界会被算2次
a = query(1, x1, y1);
b = query(1, x2, y2);
c = query(1, y1 + 1, x2 - 1);
res = a.rmax + c.sum + b.lmax;
} else {
res = query(1, x2, y1).tmax; // 最大子序列和出现在交集中
a = query(1, x1, x2 - 1);
b = query(1, x2, y2);
res = max(res, a.rmax + b.lmax);
a = query(1, x1, y1);
b = query(1, y1 + 1, y2);
res = max(res, a.rmax + b.lmax);
}
printf("%d\n", res);
}
}
return 0;
}