제출 #489624

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
489624		8e7	3단 점프 (JOI19_jumps)	C++17	100 / 100	778 ms	29460 KiB

jumps

//Challenge: Accepted
#include <iostream>
#include <algorithm>
#include <vector>
#include <utility>
#include <stack>
using namespace std;
void debug(){cout << endl;}
template<class T, class ...U> void debug(T a, U ... b){cout << a << " ", debug(b...);}
template<class T> void pary (T l, T r) {
	while (l != r) cout << *l << " ", l++;
	cout << endl;
}
#define ll long long
#define maxn 500005
#define pii pair<int, int>
#define ff first
#define ss second
#define io ios_base::sync_with_stdio(0);cin.tie(0);
int a[maxn];
int ans[maxn];
struct query{
	int l, r, id;
	query(){l = r = id = 0;}
	query(int x, int y, int z){l = x, r = y, id = z;}
} que[maxn];
struct segtree{
	int ma[4*maxn], tag[4*maxn], my[4*maxn];
	void init(int cur, int l, int r) {
		if (r <= l) return;
		if (r - l == 1) {
			ma[cur] = a[l];
			my[cur] = a[l];
			return;
		}
		int m = (l + r) / 2;
		init(cur*2, l, m), init(cur*2+1, m, r);
		ma[cur] = max(ma[cur*2], ma[cur*2+1]);
		my[cur] = max(my[cur*2], my[cur*2+1]);
	}
	void push(int cur, int l, int r) {
		if (tag[cur] == 0) return;
		ma[cur] = max(ma[cur], my[cur] + tag[cur]);
		if (r - l > 1) {
			tag[cur*2] = max(tag[cur*2], tag[cur]);
			tag[cur*2+1] = max(tag[cur*2+1], tag[cur]);
		}
		tag[cur] = 0;
	}
	void pull(int cur, int l, int r) {
		if (r - l > 1) {
			int m = (l + r) / 2;
			push(cur*2, l, m), push(cur*2+1, m, r);
			ma[cur] = max(ma[cur*2], ma[cur*2+1]);
		}
	}
	void modify(int cur, int l, int r, int ql, int qr, int x) {
		if (r <= l || ql >= r || qr <= l) return;
		push(cur, l, r);
		if (ql <= l && qr >= r) {
			tag[cur] = max(tag[cur], x);
			push(cur, l, r);
			return;
		}
		int m = (l + r) / 2;
		modify(cur*2, l, m, ql, qr, x), modify(cur*2+1, m, r, ql, qr, x);
		pull(cur, l, r);
	}
	int query(int cur,int l, int r, int ql, int qr) {
		if (r <= l || ql >= r || qr <= l) return 0;
		push(cur, l, r);
		if (ql <= l && qr >= r) {
			pull(cur, l, r);	
			return ma[cur];
		}
		int m = (l + r) / 2;
		return max(query(cur*2, l, m, ql, qr), query(cur*2+1, m, r, ql, qr));
	}
} seg;
int main() {
	io
	int n, q;
	cin >> n;
	for (int i = 1;i <= n;i++) cin >> a[i];
	cin >> q;
	for (int i = 0;i < q;i++) {
		cin >> que[i].l >> que[i].r;
		que[i].id = i;
	}
	sort(que, que + q, [&](query x, query y){return x.l > y.l;});
	stack<int> stk;	
	int ind = 0;
	seg.init(1, 1, n+1);
	for (int i = n;i >= 1;i--) {
		while (stk.size() && a[i] >= a[stk.top()]) {
			int val = a[i] + a[stk.top()];
			seg.modify(1, 1, n+1, stk.top()*2-i, n+1, val);	
			stk.pop();
		}
		if (stk.size()) {
			int val = a[i] + a[stk.top()];
			seg.modify(1, 1, n+1, stk.top()*2-i, n+1, val);	
		}
		stk.push(i);
		while (ind < q && que[ind].l == i) {
			ans[que[ind].id] = seg.query(1, 1, n+1, que[ind].l, que[ind].r+1);
			ind++;
		}
	}
	for (int i = 0;i < q;i++) cout << ans[i] << "\n";
}
/*
5
5 2 1 5 3
1
1 5


5
5 4 4 5 4
1
1 5

15
12 96 100 61 54 66 37 34 58 21 21 1 13 50 81
12
1 15
3 12
11 14
1 13
5 9
4 6
6 14
2 5
4 15
1 7
1 10
8 13
*/

• Subtask 1: 5 / 5
• Subtask 2: 14 / 14
• Subtask 3: 27 / 27
• Subtask 4: 54 / 54