Submission #1256670

#	Time	Username	Problem	Language	Result	Execution time	Memory
1256670		mingga	Triple Jump (JOI19_jumps)	C++20	100 / 100	548 ms	60052 KiB

jumps

// Author: caption_mingle
#include "bits/stdc++.h"

using namespace std;

#define ln "\n"
#define pb push_back
#define fi first
#define se second
#define all(x) (x).begin(), (x).end()
#define sz(x) ((int)(x).size())
#define ll long long
const int mod = 1e9 + 7;
const int inf = 2e9;
const int N = 5e5 + 7;
int n, q, a[N], ans[N];

vector<pair<int, int>> ev[N];

struct SEGTREE {
	int n;
	vector<int> st, lazy, ori;
	SEGTREE(int n) : n(n) {
		st.resize(n * 4 + 4, 0);
		lazy.resize(n * 4 + 4, 0);
		ori.resize(n * 4 + 4, 0);
	}
	void down(int i) {
		if(lazy[i] == 0) return;
		int x = lazy[i];
		lazy[i] = 0;
		st[i * 2] = max(st[i * 2], ori[i * 2] + x);
		st[i * 2 + 1] = max(st[i * 2 + 1], ori[i * 2 + 1] + x);
		lazy[i * 2] = max(lazy[i * 2], x);
		lazy[i * 2 + 1] = max(lazy[i * 2 + 1], x);
	}
	void init(int i, int l, int r) {
		if(l == r) {
			ori[i] = a[l];
			return;
		}
		int m = (l + r) >> 1;
		init(i * 2, l, m);
		init(i * 2 + 1, m + 1, r);
		ori[i] = max(ori[i * 2], ori[i * 2 + 1]);
	}
	void update(int i, int l, int r, int u, int v, int x) {
		if(l > v or r < u) return;
		if(u <= l and r <= v) {
			st[i] = max(st[i], ori[i] + x);
			lazy[i] = max(lazy[i], x);
			return;
		}
		down(i);
		int m = (l + r) >> 1;
		update(i * 2, l, m, u, v, x);
		update(i * 2 + 1, m + 1, r, u, v, x);
		st[i] = max(st[i * 2], st[i * 2 + 1]);
	}
	int get(int i, int l, int r, int u, int v) {
		if(l > v or r < u) return 0;
		if(u <= l and r <= v) return st[i];
		down(i);
		int m = (l + r) >> 1;
		return max(get(i * 2, l, m, u, v), get(i * 2 + 1, m + 1, r, u, v));
	}
};

signed main() {
	cin.tie(0) -> sync_with_stdio(0);
	#define task ""
	if(fopen(task ".INP", "r")) {
		freopen(task ".INP", "r", stdin);
		freopen(task ".OUT", "w", stdout);
	}
	cin >> n;
	for(int i = 1; i <= n; i++) cin >> a[i];
	cin >> q;
	for(int i = 1; i <= q; i++) {
		int l, r; cin >> l >> r;
		ev[l].pb({i, r});
	}
	SEGTREE st(n);
	st.init(1, 1, n);
	vector<int> stt;
	for(int i = n; i > 0; i--) {
		while(sz(stt) and a[stt.back()] < a[i]) {
			int j = stt.back();
			stt.pop_back();
			int l = 2 * j - i;
			st.update(1, 1, n, l, n, a[i] + a[j]);
		}
		if(sz(stt)) {
			int j = stt.back();
			int l = 2 * j - i;
			st.update(1, 1, n, l, n, a[i] + a[j]);
		}
		stt.pb(i);
		for(auto [id, r] : ev[i]) {
			ans[id] = st.get(1, 1, n, i, r);
		}
	}
	for(int i = 1; i <= q; i++) cout << ans[i] << ln;
    cerr << "\nTime: " << clock() * 1000 / CLOCKS_PER_SEC;
}

Compilation message (stderr)

jumps.cpp: In function 'int main()':
jumps.cpp:73:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   73 |                 freopen(task ".INP", "r", stdin);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
jumps.cpp:74:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   74 |                 freopen(task ".OUT", "w", stdout);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

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