Submission #1145413

#	Time	Username	Problem	Language	Result	Execution time	Memory
1145413		Trisanu_Das	Two Antennas (JOI19_antennas)	C++20	35 / 100	3096 ms	38168 KiB

antennas

#include <bits/stdc++.h>
typedef long long ll;
using namespace std;

const int INF = 1e9;

int n, a[200001], b[200001], h[200001], mx[200001], ans[200001];
vector<int> ins[400001], rem[400001];
int segtree[800001];
vector<pair<int, int>> Q[200001];

void build(int node = 1, int l = 1, int r = n) {
    segtree[node] = -INF;
    if (l != r) {
        int mid = (l + r) / 2;
        build(node * 2, l, mid);
        build(node * 2 + 1, mid + 1, r);
    }
}

void update(int pos, int val, int node = 1, int l = 1, int r = n) {
    if (l == r) segtree[node] = val;
    else {
        int mid = (l + r) / 2;
        if (pos > mid) update(pos, val, node * 2 + 1, mid + 1, r);
        else update(pos, val, node * 2, l, mid);
        segtree[node] = max(segtree[node * 2], segtree[node * 2 + 1]);
    }
}

int query(int x, int y, int node = 1, int l = 1, int r = n) {
    if (l > y || r < x) return -INF;
    if (l >= x && r <= y) return segtree[node];
    int mid = (l + r) / 2;
    return max(query(x, y, node * 2, l, mid),
               query(x, y, node * 2 + 1, mid + 1, r));
}

void solve(int l, int r) {
    build();
    for (int i = l; i <= r; i++) {
        for (int j : ins[i]) update(j, h[j]);
        mx[i] = max(mx[i], query(i - b[i], i - a[i]) - h[i]);
        for (int j : rem[i]) update(j, -INF);
    }
}

signed main() {
    cin.tie(0)->sync_with_stdio(0);
    cin >> n;
    for (int i = 1; i <= n; i++) cin >> h[i] >> a[i] >> b[i];
    int q; cin >> q;
    for (int i = 1; i <= q; i++) {
        int l, r; cin >> l >> r;
        Q[l].push_back({r, i});
    }
    for (int i = n; i; i--) {
        ins[i + a[i]].push_back(i);
        rem[i + b[i]].push_back(i);
        if (Q[i].size()) {
            sort(Q[i].begin(), Q[i].end());
            memset(mx, -1, sizeof mx);
            solve(i, n);
            for (int j = i; j <= n; j++) h[j] *= -1;
            solve(i, n);
            for (int j = i; j <= n; j++) h[j] *= -1;
            for (int j = 0; j < Q[i].size(); j++) {
                if (!j) ans[Q[i][j].second] = *max_element(mx + i, mx + Q[i][j].first + 1);
                else ans[Q[i][j].second] = max(ans[Q[i][j - 1].second], *max_element(mx + Q[i][j - 1].first, mx + Q[i][j].first + 1));
            }
        }
    }
    for (int i = 1; i <= q; i++) cout << ans[i] << '\n';
}

• Subtask 1: 2 / 2
• Subtask 2: 11 / 11
• Subtask 3: 22 / 22
• Subtask 4: 0 / 65