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- #include <iostream>
- #include <map>
- #include <string>
- #include <vector>
- #include <algorithm>
- using namespace std;
- const int maxn = 1e5 + 10;
- const int INF = 2e9;
- int n, a[maxn];
- pair<int, int> segment_tree[3 * maxn];
- pair<int, int> merge_nodes(pair<int, int> A, pair<int, int> B) {
- vector<int> v{A.first, A.second, B.first, B.second};
- sort(v.begin(), v.end());
- return {v[2], v[3]};
- }
- void build_tree(int L, int R, int node) {
- if(L == R) {
- segment_tree[node] = {a[L], -INF};
- }
- else {
- int middle = (L + R) / 2;
- build_tree(L, middle, 2 * node);
- build_tree(middle + 1, R, 2 * node + 1);
- segment_tree[node] = merge_nodes(segment_tree[2 * node], segment_tree[2 * node + 1]);
- }
- }
- pair<int, int> query(int i, int j, int L, int R, int node) {
- if(i <= L and R <= j) {
- return segment_tree[node];
- }
- if(R < i or j < L) {
- return {-INF, -INF};
- }
- int middle = (L + R) / 2;
- pair<int, int> left_side = query(i, j, L, middle, 2 * node);
- pair<int, int> right_side = query(i, j, middle + 1, R, 2 * node + 1);
- return merge_nodes(left_side, right_side);
- }
- void update(int idx, int new_val, int L, int R, int node) {
- if(L == R) {
- segment_tree[node] = {new_val, -INF};
- return;
- }
- int middle = (L + R) / 2;
- if(idx <= middle) {
- update(idx, new_val, L, middle, 2 * node);
- }
- else {
- update(idx, new_val, middle + 1, R, 2 * node + 1);
- }
- segment_tree[node] = merge_nodes(segment_tree[2 * node], segment_tree[2 * node + 1]);
- }
- int main() {
- ios_base::sync_with_stdio(false);
- cin >> n;
- for(int i = 0; i < n; i++) {
- cin >> a[i];
- }
- build_tree(0, n - 1, 1);
- int q;
- cin >> q;
- for(int i = 0; i < q; i++) {
- char c;
- cin >> c;
- if(c == 'Q') {
- int x, y;
- cin >> x >> y;
- pair<int, int> res = query(x - 1, y - 1, 0, n - 1, 1);
- cout << res.first + res.second << endl;
- }
- else {
- int idx, val;
- cin >> idx >> val;
- update(idx - 1, val, 0, n - 1, 1);
- }
- }
- return 0;
- }
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