Submission #219714

#	Time	Username	Problem	Language	Result	Execution time	Memory
219714		manh9203	Two Antennas (JOI19_antennas)	C++17	100 / 100	945 ms	48108 KiB

antennas

#include<bits/stdc++.h>

using namespace std;

#define ll long long
const int N = 2e5 + 5;
const int INF = 1e9 + 5;

int n, q;
int H[N], A[N], B[N];
int L[N], R[N];
int ans[N];
vector<int> queRy[N];
vector<int> add[N], sub[N];

struct node {
	int D, C, lz;
} st[4 * N];

void build(int id, int l, int r) {
	st[id].lz = INF;
	if (l == r) {
		st[id].D = st[id].C = -INF;
		return;
	}
	int mid = (l + r) >> 1;
	build(id << 1, l, mid);
	build(id << 1 | 1, mid + 1, r);
	st[id].D = max(st[id << 1].D, st[id << 1 | 1].D);
	st[id].C = max(st[id << 1].C, st[id << 1 | 1].C);
}

void pushDown(int id, int l, int r) {
	if (st[id].lz != INF) {
		st[id].D = max(st[id].D, st[id].C - st[id].lz);
		if (l < r) {
			st[id << 1].lz = min(st[id << 1].lz, st[id].lz);
			st[id << 1 | 1].lz = min(st[id << 1 | 1].lz, st[id].lz);
		}
		st[id].lz = INF;
	}
}

void update(int id, int l, int r, int i, int j, int x) {
	pushDown(id, l, r);
	if (l > j || r < i || i > j) {
		return;
	}
	if (l >= i && r <= j) {
		st[id].lz = x;
		pushDown(id, l, r);
		return;
	}
	int mid = (l + r) >> 1;
	update(id << 1, l, mid, i, j, x);
	update(id << 1 | 1, mid + 1, r, i, j, x);
	st[id].D = max(st[id << 1].D, st[id << 1 | 1].D);
	st[id].C = max(st[id << 1].C, st[id << 1 | 1].C);
}

void updPos(int id, int l, int r, int i, int x) {
	pushDown(id, l, r);
	if (l > i || r < i) {
		return;
	}
	if (l == r) {
		st[id].C = x;
		return;
	}
	int mid = (l + r) >> 1;
	updPos(id << 1, l, mid, i, x);
	updPos(id << 1 | 1, mid + 1, r, i, x);
	st[id].D = max(st[id << 1].D, st[id << 1 | 1].D);
	st[id].C = max(st[id << 1].C, st[id << 1 | 1].C);
}

int get(int id, int l, int r, int i, int j) {
	pushDown(id, l, r);
	if (l > j || r < i || i > j) {
		return -INF;
	}
	if (l >= i && r <= j) {
		return st[id].D;
	}
	int mid = (l + r) >> 1;
	return max(get(id << 1, l, mid, i, j), get(id << 1 | 1, mid + 1, r, i, j));
}


int main() {
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	
	cin >> n;
	for (int i = 1; i <= n; i++) {
		cin >> H[i] >> A[i] >> B[i];
		add[min(n + 1, i + A[i])].push_back(i);
		sub[min(n + 1, i + B[i])].push_back(i);
	}
	cin >> q;
	for (int i = 1; i <= q; i++) {
		cin >> L[i] >> R[i];
		queRy[R[i]].push_back(i);
		ans[i] = -INF;
	}
	
	build(1, 1, n);
	for (int i = 1; i <= n; i++) {
		for (int j : add[i]) {
			updPos(1, 1, n, j, H[j]);
		}
		update(1, 1, n, max(0, i - B[i]), max(0, i - A[i]), H[i]);
		for (int j: queRy[i]) {
			ans[j] = max(ans[j], get(1, 1, n, L[j], i));
		}
		for (int j: sub[i]) {
			updPos(1, 1, n, j, -INF);
		}
	}
	
	for (int i = 1; i <= n; i++) {
		add[i].clear();
		sub[i].clear();
		queRy[i].clear();
	}
	for (int i = 1; i <= n; i++) {
		add[max(0, i - A[i])].push_back(i);
		sub[max(0, i - B[i])].push_back(i);
	}
	for (int i = 1; i <= q; i++) {
		queRy[L[i]].push_back(i);
	}
	
	build(1, 1, n);
	for (int i = n; i >= 1; i--) {
		for (int j : add[i]) {
			updPos(1, 1, n, j, H[j]);
		}
		update(1, 1, n, min(n + 1, i + A[i]), min(n + 1, i + B[i]), H[i]);
		for (int j: queRy[i]) {
			ans[j] = max(ans[j], get(1, 1, n, i, R[j]));
		}
		for (int j : sub[i]) {
			updPos(1, 1, n, j, -INF);
		}
	}
	
	for (int i = 1; i <= q; i++) {
		if (ans[i] == -INF) {
			cout << "-1\n";
		} else {
			cout << ans[i] << "\n";
		}
	}
}

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