oj.uz

Submission #834586

# Submission time Handle Problem Language Result Execution time Memory
834586 2023-08-22T15:32:20 Z Elias Dynamic Diameter (CEOI19_diameter) C++17
31 / 100
 5000 ms 659920 KB 
#ifndef _DEBUG
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#endif

#include <bits/stdc++.h>

using namespace std;

#define int long long
#define all(x) (x).begin(), (x).end()

template <class T>
istream &operator>>(istream &in, vector<T> &a)
{
	for (T &x : a)
		in >> x;
	return in;
}

template <class T>
ostream &operator<<(ostream &out, const vector<T> &a)
{
	for (T x : a)
		out << x << " ";
	out << "\n";
	return out;
}

struct SegTree
{
	pair<int, int> get(int l, int r)
	{
		return get(0, n, 0, l, r);
	}
	void inc(int l, int r, int x)
	{
		inc(0, n, 0, l, r, x);
	}

	SegTree(const vector<int> &a)
	{
		n = a.size();
		updates = vector<int>(4 * n);
		b = vector<pair<int, int>>(4 * n);
		build(0, n, 0, a);
	}

	SegTree() {}

private:
	int n = 0;
	vector<pair<int, int>> b = {};
	vector<int> updates = {};

	void push(int l, int r, int i)
	{
		if (l + 1 == r)
			return;
		updates[i * 2 + 1] += updates[i];
		updates[i * 2 + 2] += updates[i];
		b[i * 2 + 1].first += updates[i];
		b[i * 2 + 2].first += updates[i];
		updates[i] = 0;
	}

	pair<int, int> build(int l, int r, int i, const vector<int> &a)
	{
		if (l + 1 == r)
			return b[i] = pair<int, int>{a[l], l};
		int m = (l + r) / 2;
		return b[i] = max(build(l, m, i * 2 + 1, a), build(m, r, i * 2 + 2, a));
	}

	pair<int, int> get(int l, int r, int i, int ql, int qr)
	{
		if (l >= qr || r <= ql)
			return {LLONG_MIN / 2, -1};
		if (l >= ql && r <= qr)
			return b[i];
		push(l, r, i);
		int m = (l + r) / 2;
		return max(get(l, m, i * 2 + 1, ql, qr), get(m, r, i * 2 + 2, ql, qr));
	}

	pair<int, int> inc(int l, int r, int i, int ul, int ur, int x)
	{
		if (l >= ur || r <= ul)
			return b[i];
		if (l >= ul && r <= ur)
		{
			updates[i] += x;
			b[i].first += x;
			return b[i];
		}
		push(l, r, i);
		int m = (l + r) / 2;
		return b[i] = max(inc(l, m, i * 2 + 1, ul, ur, x), inc(m, r, i * 2 + 2, ul, ur, x));
	}
};

struct Tree
{
	int n;

	map<int, vector<pair<int, int>>> edges;

	map<int, int> pre;
	map<int, int> subtree;
	map<int, int> initial_parent;
	vector<int> pre_order;

	vector<int> pre_dist;

	int timer = 0;
	int centroid = -1;

	SegTree pre_dist_seg;

	int find_centroid(int i, int p = -1)
	{
		int subtree_size = 1;
		int largest_subtree = 0;

		for (auto [c, D] : edges[i])
		{
			if (c != p)
			{
				int sub = find_centroid(c, i);
				subtree_size += sub;
				largest_subtree = max(largest_subtree, sub);
			}
		}

		if (largest_subtree <= n / 2 && n - subtree_size <= n / 2)
			centroid = i;

		return subtree_size;
	}

	void get_edges(int i, int p, map<int, vector<pair<int, int>>> &out)
	{
		for (auto [c, d] : edges[i])
		{
			if (c == centroid)
				continue;
			out[i].push_back({c, d});
			if (c != p)
				get_edges(c, i, out);
		}
	}

	int dfs(int i, int d = 0, int p = -1)
	{
		pre[i] = timer++;
		pre_order.push_back(i);
		pre_dist[pre[i]] = d;

		int subtree_size = 1;

		if (p == -1)
			initial_parent[i] = -1;
		else if (initial_parent[p] == -1)
			initial_parent[i] = i;
		else
			initial_parent[i] = initial_parent[p];

		for (auto [c, D] : edges[i])
		{
			if (c != p)
			{
				subtree_size += dfs(c, d + D, i);
			}
		}

		subtree[i] = subtree_size;

		return subtree_size;
	}

	vector<map<int, vector<pair<int, int>>>> split()
	{
		vector<map<int, vector<pair<int, int>>>> out;
		for (auto [c, d] : edges[centroid])
		{
			map<int, vector<pair<int, int>>> subset;
			get_edges(c, centroid, subset);
			out.push_back(move(subset));
		}
		return out;
	}

	Tree(map<int, vector<pair<int, int>>> edges) : edges{edges}
	{
		n = edges.size();
		pre_dist = vector<int>(n);

		int start;

		for (auto [i, c] : edges)
		{
			start = i;
			break;
		}

		find_centroid(start);

		assert(centroid != -1);

		dfs(centroid);

		pre_dist_seg = SegTree(pre_dist);
	}

	int update(int a, int b, int c)
	{
		if (subtree.count(a) != 0 && subtree.count(b) != 0)
		{
			if (pre[a] > pre[b])
				swap(a, b);

			int dist_lower = pre_dist_seg.get(pre[b], pre[b] + 1).first;
			int dist_upper = pre_dist_seg.get(pre[a], pre[a] + 1).first;

			int old_weight = dist_lower - dist_upper;

			int delta = c - old_weight;
			pre_dist_seg.inc(pre[b], pre[b] + subtree[b], delta);
		}

		auto [dist, i] = pre_dist_seg.get(0, n);
		int bad_child = initial_parent[pre_order[i]];

		auto dist2 = pre_dist_seg.get(0, pre[bad_child]).first;
		auto dist3 = pre_dist_seg.get(pre[bad_child] + subtree[bad_child], n).first;

		return dist + max({dist2, dist3, 0ll});
	}
};

signed main()
{
	cin.tie(0);
	ios_base::sync_with_stdio(false);

	int n, q, w;
	cin >> n >> q >> w;

	map<int, vector<pair<int, int>>> edges;

	vector<pair<int, int>> all_edges;

	for (int i = 0; i < n - 1; i++)
	{
		int a, b, c;
		cin >> a >> b >> c;
		a--, b--;

		edges[a].push_back({b, c});
		edges[b].push_back({a, c});

		all_edges.push_back({a, b});
	}

	vector<Tree> subtrees;
	subtrees.push_back(Tree(edges));

	queue<int> todo;
	todo.push(0);

	vector<vector<int>> trees_using(n, {0});

	while (todo.size())
	{
		int index = todo.front();
		todo.pop();

		auto out = subtrees[index].split();
		for (auto &x : out)
		{
			if (x.size() > 1)
			{
				int new_index = subtrees.size();
				todo.push(new_index);
				subtrees.push_back(Tree(x));
				for (auto [i, c] : x)
				{
					if (trees_using[i].back() != new_index)
						trees_using[i].push_back(new_index);
				}
			}
		}
	}

	vector<int> subtree_result(subtrees.size());

	set<pair<int, int>> results;

	for (int i = 0; i < subtrees.size(); i++)
	{
		subtree_result[i] = subtrees[i].update(-1, -1, -1);
		results.insert({subtree_result[i], i});
	}

	int last = 0;

	while (q--)
	{
		int d, e;
		cin >> d >> e;
		d = (d + last) % (n - 1);
		e = (e + last) % w;

		auto [a, b] = all_edges[d];

		int out = 0;

		for (int i : trees_using[a])
		{
			results.erase({subtree_result[i], i});
			subtree_result[i] = subtrees[i].update(a, b, e);
			results.insert({subtree_result[i], i});
		}

		out = prev(results.end())->first;

		cout << out << "\n";
		last = out;
	}
}

Compilation message

diameter.cpp: In function 'int main()':
diameter.cpp:299:20: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<Tree>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  299 |  for (int i = 0; i < subtrees.size(); i++)
      |                  ~~^~~~~~~~~~~~~~~~~

Subtask #1
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 0 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 1 ms 340 KB Output is correct
10 Correct 2 ms 320 KB Output is correct
11 Correct 1 ms 340 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
13 Correct 1 ms 468 KB Output is correct
14 Correct 1 ms 468 KB Output is correct
15 Correct 1 ms 468 KB Output is correct
16 Correct 1 ms 448 KB Output is correct
17 Correct 1 ms 468 KB Output is correct
18 Correct 2 ms 576 KB Output is correct

Subtask #2
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 0 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 1 ms 340 KB Output is correct
10 Correct 2 ms 320 KB Output is correct
11 Correct 1 ms 340 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
13 Correct 1 ms 468 KB Output is correct
14 Correct 1 ms 468 KB Output is correct
15 Correct 1 ms 468 KB Output is correct
16 Correct 1 ms 448 KB Output is correct
17 Correct 1 ms 468 KB Output is correct
18 Correct 2 ms 576 KB Output is correct
19 Correct 36 ms 3028 KB Output is correct
20 Correct 41 ms 3356 KB Output is correct
21 Correct 50 ms 3872 KB Output is correct
22 Correct 73 ms 4524 KB Output is correct
23 Correct 99 ms 16060 KB Output is correct
24 Correct 138 ms 20492 KB Output is correct
25 Correct 209 ms 23172 KB Output is correct
26 Correct 179 ms 26872 KB Output is correct

Subtask #3
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 320 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 11 ms 464 KB Output is correct
5 Correct 50 ms 1468 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 1 ms 580 KB Output is correct
8 Correct 1 ms 580 KB Output is correct
9 Correct 3 ms 720 KB Output is correct
10 Correct 21 ms 956 KB Output is correct
11 Correct 100 ms 1932 KB Output is correct
12 Correct 7 ms 4180 KB Output is correct
13 Correct 7 ms 4180 KB Output is correct
14 Correct 10 ms 4180 KB Output is correct
15 Correct 38 ms 4308 KB Output is correct
16 Correct 160 ms 5192 KB Output is correct
17 Correct 182 ms 74952 KB Output is correct
18 Correct 187 ms 75080 KB Output is correct
19 Correct 199 ms 75184 KB Output is correct
20 Correct 277 ms 75104 KB Output is correct
21 Correct 507 ms 75116 KB Output is correct

Subtask #4
0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 3924 KB Output is correct
2 Correct 57 ms 4088 KB Output is correct
3 Correct 256 ms 4572 KB Output is correct
4 Correct 527 ms 5396 KB Output is correct
5 Correct 143 ms 51712 KB Output is correct
6 Correct 265 ms 51944 KB Output is correct
7 Correct 772 ms 52548 KB Output is correct
8 Correct 1416 ms 53496 KB Output is correct
9 Correct 863 ms 308000 KB Output is correct
10 Correct 1121 ms 308400 KB Output is correct
11 Correct 2174 ms 308948 KB Output is correct
12 Correct 3539 ms 309676 KB Output is correct
13 Correct 1975 ms 658108 KB Output is correct
14 Correct 2274 ms 658300 KB Output is correct
15 Correct 3640 ms 659140 KB Output is correct
16 Execution timed out 5092 ms 659920 KB Time limit exceeded
17 Halted 0 ms 0 KB -

Subtask #5
0 / 24.0

# Verdict Execution time Memory Grader output
1 Execution timed out 5067 ms 491960 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #6
0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 0 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 1 ms 340 KB Output is correct
10 Correct 2 ms 320 KB Output is correct
11 Correct 1 ms 340 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
13 Correct 1 ms 468 KB Output is correct
14 Correct 1 ms 468 KB Output is correct
15 Correct 1 ms 468 KB Output is correct
16 Correct 1 ms 448 KB Output is correct
17 Correct 1 ms 468 KB Output is correct
18 Correct 2 ms 576 KB Output is correct
19 Correct 36 ms 3028 KB Output is correct
20 Correct 41 ms 3356 KB Output is correct
21 Correct 50 ms 3872 KB Output is correct
22 Correct 73 ms 4524 KB Output is correct
23 Correct 99 ms 16060 KB Output is correct
24 Correct 138 ms 20492 KB Output is correct
25 Correct 209 ms 23172 KB Output is correct
26 Correct 179 ms 26872 KB Output is correct
27 Correct 1 ms 320 KB Output is correct
28 Correct 1 ms 212 KB Output is correct
29 Correct 1 ms 340 KB Output is correct
30 Correct 11 ms 464 KB Output is correct
31 Correct 50 ms 1468 KB Output is correct
32 Correct 1 ms 212 KB Output is correct
33 Correct 1 ms 580 KB Output is correct
34 Correct 1 ms 580 KB Output is correct
35 Correct 3 ms 720 KB Output is correct
36 Correct 21 ms 956 KB Output is correct
37 Correct 100 ms 1932 KB Output is correct
38 Correct 7 ms 4180 KB Output is correct
39 Correct 7 ms 4180 KB Output is correct
40 Correct 10 ms 4180 KB Output is correct
41 Correct 38 ms 4308 KB Output is correct
42 Correct 160 ms 5192 KB Output is correct
43 Correct 182 ms 74952 KB Output is correct
44 Correct 187 ms 75080 KB Output is correct
45 Correct 199 ms 75184 KB Output is correct
46 Correct 277 ms 75104 KB Output is correct
47 Correct 507 ms 75116 KB Output is correct
48 Correct 12 ms 3924 KB Output is correct
49 Correct 57 ms 4088 KB Output is correct
50 Correct 256 ms 4572 KB Output is correct
51 Correct 527 ms 5396 KB Output is correct
52 Correct 143 ms 51712 KB Output is correct
53 Correct 265 ms 51944 KB Output is correct
54 Correct 772 ms 52548 KB Output is correct
55 Correct 1416 ms 53496 KB Output is correct
56 Correct 863 ms 308000 KB Output is correct
57 Correct 1121 ms 308400 KB Output is correct
58 Correct 2174 ms 308948 KB Output is correct
59 Correct 3539 ms 309676 KB Output is correct
60 Correct 1975 ms 658108 KB Output is correct
61 Correct 2274 ms 658300 KB Output is correct
62 Correct 3640 ms 659140 KB Output is correct
63 Execution timed out 5092 ms 659920 KB Time limit exceeded
64 Halted 0 ms 0 KB -