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2 years ago
#include <iostream>
#include <algorithm>
#include <cstring>
#include <cstdio>
#include <unordered_map>
#include <vector>
using namespace std;
typedef long long LL;
const int N = 30010, M = 100010;
typedef pair<int, int> PII;
// 线段树结构体
struct Node {
int l, r;
LL sum; // 区间和
} tr[N << 2];
int n, m; // n个数字的原始数列m次询问
int a[N]; // 原始数组
LL ans[M]; // 问题答案
void pushup(int u) {
tr[u].sum = tr[u << 1].sum + tr[u << 1 | 1].sum;
}
void build(int u, int l, int r) {
tr[u] = {l, r};
int mid = (l + r) >> 1;
if (l == r) return;
build(u << 1, l, mid), build(u << 1 | 1, mid + 1, r);
pushup(u); // 套路其实本题不需要pushup
}
void modify(int u, int x, int v) {
if (tr[u].l == tr[u].r) {
tr[u].sum += v;
return;
}
int mid = (tr[u].l + tr[u].r) >> 1;
if (x <= mid) modify(u << 1, x, v);
if (x > mid) modify(u << 1 | 1, x, v);
pushup(u);
}
LL query(int u, int l, int r) {
if (l <= tr[u].l && tr[u].r <= r) return tr[u].sum;
LL ans = 0;
int mid = tr[u].l + tr[u].r >> 1;
if (l <= mid) ans += query(u << 1, l, r);
if (r >= mid + 1) ans += query(u << 1 | 1, l, r);
return ans;
}
int main() {
// 加快读入
ios::sync_with_stdio(false), cin.tie(0);
int T;
cin >> T;
while (T--) {
unordered_map<int, int> b;
vector<PII> q[N]; // 这是一个二维数组,单元格中是PII
memset(ans, 0, sizeof ans);
memset(tr, 0, sizeof tr);
cin >> n;
// 构建线段树
build(1, 1, n);
for (int i = 1; i <= n; i++) cin >> a[i];
cin >> m;
for (int i = 1; i <= m; i++) {
int l, r;
cin >> l >> r;
q[r].push_back({l, i}); // 以r结尾的有一个查询:{l,id=i}
}
// 图灵树
// ① 核心:一边构建,一边查询
// ② 理解为配合动态构建需要以当前的进度节点为右边界进行查询这导致了前面以右边界为索引保存PII信息
for (int i = 1; i <= n; i++) {
// 根据值利用HASH表找出此值原来的位置
// 如果有相同值出现则旧位置上减去a[i],然后更新HASH在新位置上+a[i]
if (b.count(a[i])) modify(1, b[a[i]], -a[i]);
b[a[i]] = i; // 值->号
modify(1, i, a[i]);
// 枚举以i为右端点的查询
for (auto c : q[i]) ans[c.second] = query(1, c.first, i);
}
// 输出
for (int i = 1; i <= m; i++) printf("%lld\n", ans[i]);
}
return 0;
}