Submission #721601

#	Time	Username	Problem	Language	Result	Execution time	Memory
721601		pavement	별자리 3 (JOI20_constellation3)	C++17	100 / 100	710 ms	103500 KiB

constellation3

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
#define int long long
#define mp make_pair
#define mt make_tuple
#define pb push_back
#define ppb pop_back
#define eb emplace_back
#define g0(a) get<0>(a)
#define g1(a) get<1>(a)
#define g2(a) get<2>(a)
#define g3(a) get<3>(a)
#define g4(a) get<4>(a)
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
using db = double;
using ll = long long;
using ld = long double;
using ii = pair<int, int>;
using iii = tuple<int, int, int>;
using iiii = tuple<int, int, int, int>;
using iiiii = tuple<int, int, int, int, int>;
template<class key, class value = null_type, class cmp = less<key> >
using ordered_set = tree<key, value, cmp, rb_tree_tag, tree_order_statistics_node_update>;

int N, M, idx, tot, A[200005], X[200005], Y[200005], C[200005], min_l[200005], min_r[200005], lab[200005], L[200005], R[200005], H[200005], ft1[200005], ft2[200005], a[200005], b[200005], sz[200005], anc[25][200005];
stack<int> S;
vector<int> adj[200005], vec[200005];

void construct(int l, int r, int par = -1) {
	if (l > r) return;
	int cur = ++idx;
	if (par != -1) {
		adj[par].pb(cur);
	}
	int mid = -1;
	for (int i = l, j = r; i <= j; i++, j--) {
		if (min_l[i] < l && min_r[i] > r) {
			mid = i;
			break;
		}
		if (min_l[j] < l && min_r[j] > r) {
			mid = j;
			break;
		}
	}
	assert(mid != -1);
	L[cur] = l;
	R[cur] = r;
	H[cur] = A[mid] + 1;
	lab[mid] = cur;
	construct(l, mid - 1, cur);
	construct(mid + 1, r, cur);
}

int dfs(int n) {
	for (int k = 1; k <= 20; k++) {
		if (anc[k - 1][n] == -1) break;
		anc[k][n] = anc[k - 1][anc[k - 1][n]];
	}
	for (auto u : adj[n]) {
		anc[0][u] = n;
		sz[n] += dfs(u);
	}
	return ++sz[n];
}

inline int ls(int x) { return x & -x; }

void upd1(int l, int r, int v) {
	for (; l <= N; l += ls(l)) ft1[l] += v;
	for (r++; r <= N; r += ls(r)) ft1[r] -= v;
}

void upd2(int l, int r, int v) {
	for (; l <= N; l += ls(l)) ft2[l] += v;
	for (r++; r <= N; r += ls(r)) ft2[r] -= v;
}

int qry1(int p) {
	int r = 0;
	for (; p; p -= ls(p)) r += ft1[p];
	return r;
}

int qry2(int p) {
	int r = 0;
	for (; p; p -= ls(p)) r += ft2[p];
	return r;
}

int dp(int n, int e = -1) {
	int ret = 0;
	for (auto u : adj[n]) ret += dp(u, n);
	upd1(n, n + sz[n] - 1, ret);
	for (auto i : vec[n])
		ret = max(ret, qry1(a[i]) + qry1(b[i]) - qry1(n) - (qry2(a[i]) + qry2(b[i]) - qry2(n)) + C[i]);
	upd2(n, n + sz[n] - 1, ret);
	return ret;
}

main() {
	memset(anc, -1, sizeof anc);
	ios::sync_with_stdio(0);
	cin.tie(0);
	cin >> N;
	for (int i = 1; i <= N; i++) {
		cin >> A[i];
	}
	cin >> M;
	for (int i = 1; i <= M; i++) {
		cin >> X[i] >> Y[i] >> C[i];
		tot += C[i];
	}
	for (int i = 1; i <= N; i++) {
		while (!S.empty() && A[S.top()] <= A[i]) S.pop();
		min_l[i] = (S.empty() ? 0 : S.top());
		S.push(i);
	}
	while (!S.empty()) S.pop();
	for (int i = N; i >= 1; i--) {
		while (!S.empty() && A[S.top()] <= A[i]) S.pop();
		min_r[i] = (S.empty() ? N + 1 : S.top());
		S.push(i);
	}
	construct(1, N);
	dfs(1);
	for (int i = 1; i <= M; i++) {
		assert(H[lab[X[i]]] <= Y[i]);
		int cur = lab[X[i]];
		for (int k = 20; k >= 0; k--) {
			if (anc[k][cur] != -1 && H[anc[k][cur]] <= Y[i]) {
				cur = anc[k][cur];
			}
		}
		a[i] = lab[X[i]];
		b[i] = cur;
		vec[b[i]].pb(i);
	}
	cout << tot - dp(1) << '\n';
}

Compilation message (stderr)

constellation3.cpp:104:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  104 | main() {
      | ^~~~

• Subtask 1: 14 / 14
• Subtask 2: 21 / 21
• Subtask 3: 65 / 65