Submission #872576

#	Time	Username	Problem	Language	Result	Execution time	Memory
872576		serifefedartar	Two Antennas (JOI19_antennas)	C++17	100 / 100	671 ms	86252 KiB

antennas

#include <bits/stdc++.h>
using namespace std;
 
#define fast ios::sync_with_stdio(0);cin.tie(0);
#define s second
#define f first
typedef long long ll;
const ll MOD = 1e9+9;
const ll LOGN = 20; 
const ll MAXN = 2e5 + 100;

struct Ant {
	ll H, A, B;
	Ant() { }
	void read() {
		cin >> H >> A >> B;		
	}
};

vector<Ant> antenna;
vector<pair<int,int>> query;
ll sg[4*MAXN], negative[4*MAXN], positive[4*MAXN], lazy[4*MAXN], ans[MAXN];
vector<int> add[2*MAXN], rem[2*MAXN];
vector<pair<int,int>> qs[2*MAXN];
int n, q;
void push(int k, int a, int b) {
	sg[k] = max(sg[k], negative[k] + lazy[k]);
	if (a != b) {
		lazy[2*k] = max(lazy[2*k], lazy[k]);
		lazy[2*k+1] = max(lazy[2*k+1], lazy[k]);
	}
	lazy[k] = 0;
}

void update_pos(int k, int a, int b, int q_l, int q_r, ll val) {
	push(k, a, b);
	if (b < q_l || a > q_r)
		return ;
	if (q_l <= a && b <= q_r) {
		lazy[k] = val;
		push(k, a, b);
		return ;
	}
	update_pos(2*k, a, (a+b)/2, q_l, q_r, val);
	update_pos(2*k+1, (a+b)/2+1, b, q_l, q_r, val);
	sg[k] = max(sg[k], max(sg[2*k], sg[2*k+1]));
}

void update(int k, int a, int b, int plc, ll val) {
	push(k, a, b);
	if (b < plc || a > plc)
		return ;
	if (a == b) {
		negative[k] = val;
		return ;
	}
	update(2*k, a, (a+b)/2, plc, val);
	update(2*k+1, (a+b)/2+1, b, plc, val);
	negative[k] = max(negative[2*k], negative[2*k+1]);
}

ll qry(int k, int a, int b, int q_l, int q_r) {
	push(k, a, b);
	if (b < q_l || a > q_r)
		return -1e12;
	if (q_l <= a && b <= q_r)
		return sg[k];
	return max(qry(2*k, a, (a+b)/2, q_l, q_r), 
				qry(2*k+1, (a+b)/2+1, b, q_l, q_r));
}

void solve() {
	for (int i = 0; i < 4*MAXN; i++)
		sg[i] = -1e12, negative[i] = -1e12, lazy[i] = 0;
	for (int i = 0; i < 2*MAXN; i++)
		add[i].clear(), rem[i].clear(), qs[i].clear();
	for (int i = 0; i < q; i++)
		qs[query[i].s].push_back({query[i].f, i});
	for (int i = 1; i <= n; i++)
		add[i+antenna[i].A].push_back(i), rem[i+antenna[i].B+1].push_back(i);

	for (int i = 1; i <= n; i++) {
		for (auto u : rem[i])
			update(1, 1, n, u, -1e12);
		for (auto u : add[i])
			update(1, 1, n, u, -antenna[u].H);
		if (i - antenna[i].A >= 1)
			update_pos(1, 1, n, max(1LL, i - antenna[i].B), max(1LL, i - antenna[i].A), antenna[i].H);

		for (auto u : qs[i])
			ans[u.s] = max(ans[u.s], qry(1, 1, n, u.f, i));
	}
}

int main() {
	fast
	cin >> n;

	antenna = vector<Ant>(n+1);
	for (int i = 1; i <= n; i++)
		antenna[i].read();

	int l, r;
	cin >> q;
	for (int i = 0; i < q; i++) {
		cin >> l >> r;
		query.push_back({l, r});
	}
	for (int i = 0; i < q; i++)
		ans[i] = -1;

	solve();
	for (int i = 1; i < n+1-i; i++)
		swap(antenna[i], antenna[n+1-i]);
	for (int i = 0; i < q; i++) {
		int new_s = n + 1 - query[i].f;
		int new_f = n + 1 - query[i].s;
		query[i].f = new_f; 
		query[i].s = new_s;
	}
	solve();

	for (int i = 0; i < q; i++)
		cout << ans[i] << "\n";
}

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