oj.uz

Submission #834622

# Submission time Handle Problem Language Result Execution time Memory
834622 2023-08-22T16:09:08 Z Elias Dynamic Diameter (CEOI19_diameter) C++17
49 / 100
 5000 ms 394940 KB 
#ifndef _DEBUG
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx") // codeforces
#endif

#include <bits/stdc++.h>

using namespace std;

#define int int64_t

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));
	}
};

vector<vector<pair<int, int>>> adj;
vector<bool> blocked;

struct Tree
{
	int n = 0;

	unordered_map<int, int> pre;
	unordered_map<int, int> subtree;
	unordered_map<int, int> initial_parent;

	vector<int> pre_order;
	vector<int> pre_dist;

	int timer = 0;
	int centroid = -1;

	SegTree pre_dist_seg;

	void spread(int i, int p = -1)
	{
		n++;
		for (auto [c, D] : adj[i])
		{
			if (c != p && !blocked[c])
			{
				spread(c, i);
			}
		}
	}

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

		for (auto [c, D] : adj[i])
		{
			if (c != p && !blocked[c])
			{
				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;
	}

	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] : adj[i])
		{
			if (c != p && !blocked[c])
			{
				subtree_size += dfs(c, d + D, i);
			}
		}

		subtree[i] = subtree_size;

		return subtree_size;
	}

	vector<int> split()
	{
		blocked[centroid] = true;
		vector<int> out;
		for (auto [c, d] : adj[centroid])
		{
			if (!blocked[c])
				out.push_back(c);
		}
		return out;
	}

	Tree(int start)
	{
		spread(start);
		pre_dist = vector<int>(n);

		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, 0l});
	}
};

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

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

	adj.resize(n);
	blocked.resize(n);

	vector<pair<int, int>> all_edges;

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

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

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

	vector<Tree> subtrees;
	subtrees.push_back(Tree(0));

	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)
		{
			Tree new_tree(x);
			if (new_tree.n > 1)
			{
				int new_index = subtrees.size();
				todo.push(new_index);

				for (auto i : new_tree.pre_order)
				{
					if (trees_using[i].back() != new_index)
						trees_using[i].push_back(new_index);
				}

				subtrees.push_back(move(Tree(x)));
			}
		}
	}

	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) % int(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:296:20: warning: comparison of integer expressions of different signedness: 'int64_t' {aka 'long int'} and 'std::vector<Tree>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  296 |  for (int i = 0; i < subtrees.size(); i++)
      |                  ~~^~~~~~~~~~~~~~~~~

Subtask #1
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 212 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 1 ms 340 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 340 KB Output is correct
14 Correct 1 ms 340 KB Output is correct
15 Correct 1 ms 340 KB Output is correct
16 Correct 1 ms 468 KB Output is correct
17 Correct 1 ms 468 KB Output is correct
18 Correct 1 ms 468 KB Output is correct

Subtask #2
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 212 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 1 ms 340 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 340 KB Output is correct
14 Correct 1 ms 340 KB Output is correct
15 Correct 1 ms 340 KB Output is correct
16 Correct 1 ms 468 KB Output is correct
17 Correct 1 ms 468 KB Output is correct
18 Correct 1 ms 468 KB Output is correct
19 Correct 22 ms 2088 KB Output is correct
20 Correct 25 ms 2268 KB Output is correct
21 Correct 30 ms 2524 KB Output is correct
22 Correct 34 ms 2900 KB Output is correct
23 Correct 55 ms 10320 KB Output is correct
24 Correct 73 ms 12888 KB Output is correct
25 Correct 93 ms 14608 KB Output is correct
26 Correct 105 ms 16964 KB Output is correct

Subtask #3
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 2 ms 340 KB Output is correct
4 Correct 10 ms 356 KB Output is correct
5 Correct 46 ms 740 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 1 ms 468 KB Output is correct
8 Correct 1 ms 468 KB Output is correct
9 Correct 2 ms 468 KB Output is correct
10 Correct 15 ms 548 KB Output is correct
11 Correct 88 ms 920 KB Output is correct
12 Correct 4 ms 2260 KB Output is correct
13 Correct 4 ms 2260 KB Output is correct
14 Correct 6 ms 2260 KB Output is correct
15 Correct 22 ms 2360 KB Output is correct
16 Correct 91 ms 2728 KB Output is correct
17 Correct 84 ms 40672 KB Output is correct
18 Correct 81 ms 40624 KB Output is correct
19 Correct 82 ms 40620 KB Output is correct
20 Correct 107 ms 40668 KB Output is correct
21 Correct 265 ms 40572 KB Output is correct

Subtask #4
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 2516 KB Output is correct
2 Correct 40 ms 2668 KB Output is correct
3 Correct 173 ms 2764 KB Output is correct
4 Correct 355 ms 3144 KB Output is correct
5 Correct 79 ms 31364 KB Output is correct
6 Correct 160 ms 31540 KB Output is correct
7 Correct 443 ms 31716 KB Output is correct
8 Correct 840 ms 31936 KB Output is correct
9 Correct 459 ms 184016 KB Output is correct
10 Correct 583 ms 184028 KB Output is correct
11 Correct 1174 ms 184280 KB Output is correct
12 Correct 1952 ms 184660 KB Output is correct
13 Correct 968 ms 391196 KB Output is correct
14 Correct 1134 ms 391200 KB Output is correct
15 Correct 1843 ms 391436 KB Output is correct
16 Correct 2742 ms 391708 KB Output is correct
17 Correct 4645 ms 391772 KB Output is correct

Subtask #5
0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 3833 ms 301600 KB Output is correct
2 Correct 3875 ms 310704 KB Output is correct
3 Correct 3815 ms 308340 KB Output is correct
4 Correct 3914 ms 312764 KB Output is correct
5 Correct 3691 ms 288412 KB Output is correct
6 Correct 3154 ms 181064 KB Output is correct
7 Execution timed out 5101 ms 394940 KB Time limit exceeded
8 Halted 0 ms 0 KB -

Subtask #6
0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 212 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 1 ms 340 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 340 KB Output is correct
14 Correct 1 ms 340 KB Output is correct
15 Correct 1 ms 340 KB Output is correct
16 Correct 1 ms 468 KB Output is correct
17 Correct 1 ms 468 KB Output is correct
18 Correct 1 ms 468 KB Output is correct
19 Correct 22 ms 2088 KB Output is correct
20 Correct 25 ms 2268 KB Output is correct
21 Correct 30 ms 2524 KB Output is correct
22 Correct 34 ms 2900 KB Output is correct
23 Correct 55 ms 10320 KB Output is correct
24 Correct 73 ms 12888 KB Output is correct
25 Correct 93 ms 14608 KB Output is correct
26 Correct 105 ms 16964 KB Output is correct
27 Correct 0 ms 212 KB Output is correct
28 Correct 0 ms 212 KB Output is correct
29 Correct 2 ms 340 KB Output is correct
30 Correct 10 ms 356 KB Output is correct
31 Correct 46 ms 740 KB Output is correct
32 Correct 0 ms 212 KB Output is correct
33 Correct 1 ms 468 KB Output is correct
34 Correct 1 ms 468 KB Output is correct
35 Correct 2 ms 468 KB Output is correct
36 Correct 15 ms 548 KB Output is correct
37 Correct 88 ms 920 KB Output is correct
38 Correct 4 ms 2260 KB Output is correct
39 Correct 4 ms 2260 KB Output is correct
40 Correct 6 ms 2260 KB Output is correct
41 Correct 22 ms 2360 KB Output is correct
42 Correct 91 ms 2728 KB Output is correct
43 Correct 84 ms 40672 KB Output is correct
44 Correct 81 ms 40624 KB Output is correct
45 Correct 82 ms 40620 KB Output is correct
46 Correct 107 ms 40668 KB Output is correct
47 Correct 265 ms 40572 KB Output is correct
48 Correct 8 ms 2516 KB Output is correct
49 Correct 40 ms 2668 KB Output is correct
50 Correct 173 ms 2764 KB Output is correct
51 Correct 355 ms 3144 KB Output is correct
52 Correct 79 ms 31364 KB Output is correct
53 Correct 160 ms 31540 KB Output is correct
54 Correct 443 ms 31716 KB Output is correct
55 Correct 840 ms 31936 KB Output is correct
56 Correct 459 ms 184016 KB Output is correct
57 Correct 583 ms 184028 KB Output is correct
58 Correct 1174 ms 184280 KB Output is correct
59 Correct 1952 ms 184660 KB Output is correct
60 Correct 968 ms 391196 KB Output is correct
61 Correct 1134 ms 391200 KB Output is correct
62 Correct 1843 ms 391436 KB Output is correct
63 Correct 2742 ms 391708 KB Output is correct
64 Correct 4645 ms 391772 KB Output is correct
65 Correct 3833 ms 301600 KB Output is correct
66 Correct 3875 ms 310704 KB Output is correct
67 Correct 3815 ms 308340 KB Output is correct
68 Correct 3914 ms 312764 KB Output is correct
69 Correct 3691 ms 288412 KB Output is correct
70 Correct 3154 ms 181064 KB Output is correct
71 Execution timed out 5101 ms 394940 KB Time limit exceeded
72 Halted 0 ms 0 KB -