oj.uz

Submission #834636

# Submission time Handle Problem Language Result Execution time Memory
834636 2023-08-22T16:17:23 Z Elias Dynamic Diameter (CEOI19_diameter) C++17
100 / 100
 4728 ms 349348 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;
vector<vector<int>> pre;

struct Tree
{
	int n = 0;
	int level = 0;

	unordered_map<int, int> pre;
	vector<int> subtree;
	vector<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[pre[i]] = -1;
		else if (initial_parent[pre[p]] == -1)
			initial_parent[pre[i]] = i;
		else
			initial_parent[pre[i]] = initial_parent[pre[p]];

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

		subtree[pre[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, int level) : level(level)
	{
		spread(start);
		pre_dist = initial_parent = subtree = 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 (pre.count(a) != 0 && pre.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[pre[b]], delta);
		}

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

		auto dist2 = pre_dist_seg.get(0, pre[bad_child]).first;
		auto dist3 = pre_dist_seg.get(pre[bad_child] + subtree[pre[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);
	pre = vector<vector<int>>(30, vector<int>(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, 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, subtrees[index].level + 1);
			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(new_tree));
			}
		}
	}

	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:299:20: 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]
  299 |  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 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 0 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 340 KB Output is correct
17 Correct 1 ms 340 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 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 0 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 340 KB Output is correct
17 Correct 1 ms 340 KB Output is correct
18 Correct 1 ms 468 KB Output is correct
19 Correct 21 ms 1876 KB Output is correct
20 Correct 23 ms 1876 KB Output is correct
21 Correct 26 ms 2132 KB Output is correct
22 Correct 29 ms 2516 KB Output is correct
23 Correct 41 ms 8928 KB Output is correct
24 Correct 62 ms 10972 KB Output is correct
25 Correct 58 ms 12000 KB Output is correct
26 Correct 63 ms 13804 KB Output is correct

Subtask #3
7.0 / 7.0

# 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 340 KB Output is correct
4 Correct 10 ms 340 KB Output is correct
5 Correct 47 ms 708 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 1 ms 596 KB Output is correct
8 Correct 1 ms 596 KB Output is correct
9 Correct 2 ms 596 KB Output is correct
10 Correct 16 ms 764 KB Output is correct
11 Correct 69 ms 940 KB Output is correct
12 Correct 4 ms 3152 KB Output is correct
13 Correct 4 ms 3152 KB Output is correct
14 Correct 6 ms 3152 KB Output is correct
15 Correct 22 ms 3152 KB Output is correct
16 Correct 94 ms 3576 KB Output is correct
17 Correct 78 ms 56804 KB Output is correct
18 Correct 79 ms 56804 KB Output is correct
19 Correct 100 ms 56744 KB Output is correct
20 Correct 109 ms 56756 KB Output is correct
21 Correct 201 ms 56780 KB Output is correct

Subtask #4
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 2132 KB Output is correct
2 Correct 37 ms 2260 KB Output is correct
3 Correct 162 ms 2416 KB Output is correct
4 Correct 333 ms 2784 KB Output is correct
5 Correct 44 ms 25640 KB Output is correct
6 Correct 99 ms 25684 KB Output is correct
7 Correct 372 ms 25840 KB Output is correct
8 Correct 675 ms 26332 KB Output is correct
9 Correct 228 ms 146836 KB Output is correct
10 Correct 357 ms 146912 KB Output is correct
11 Correct 915 ms 147136 KB Output is correct
12 Correct 1500 ms 147464 KB Output is correct
13 Correct 493 ms 309920 KB Output is correct
14 Correct 623 ms 309984 KB Output is correct
15 Correct 1251 ms 310340 KB Output is correct
16 Correct 2098 ms 310640 KB Output is correct
17 Correct 3750 ms 310552 KB Output is correct

Subtask #5
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 2880 ms 245740 KB Output is correct
2 Correct 3091 ms 252528 KB Output is correct
3 Correct 2962 ms 250676 KB Output is correct
4 Correct 3034 ms 253172 KB Output is correct
5 Correct 2972 ms 236576 KB Output is correct
6 Correct 2573 ms 158100 KB Output is correct
7 Correct 4280 ms 312408 KB Output is correct
8 Correct 4033 ms 312364 KB Output is correct
9 Correct 4083 ms 312476 KB Output is correct
10 Correct 4100 ms 310856 KB Output is correct
11 Correct 4013 ms 292144 KB Output is correct
12 Correct 3493 ms 190204 KB Output is correct
13 Correct 4463 ms 345184 KB Output is correct
14 Correct 4387 ms 345196 KB Output is correct
15 Correct 4417 ms 345488 KB Output is correct
16 Correct 4372 ms 343372 KB Output is correct
17 Correct 4214 ms 321008 KB Output is correct
18 Correct 3697 ms 202432 KB Output is correct
19 Correct 4455 ms 345384 KB Output is correct
20 Correct 4299 ms 345280 KB Output is correct
21 Correct 4728 ms 349348 KB Output is correct
22 Correct 4576 ms 347492 KB Output is correct
23 Correct 4473 ms 325204 KB Output is correct
24 Correct 3904 ms 206584 KB Output is correct

Subtask #6
27.0 / 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 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 0 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 340 KB Output is correct
17 Correct 1 ms 340 KB Output is correct
18 Correct 1 ms 468 KB Output is correct
19 Correct 21 ms 1876 KB Output is correct
20 Correct 23 ms 1876 KB Output is correct
21 Correct 26 ms 2132 KB Output is correct
22 Correct 29 ms 2516 KB Output is correct
23 Correct 41 ms 8928 KB Output is correct
24 Correct 62 ms 10972 KB Output is correct
25 Correct 58 ms 12000 KB Output is correct
26 Correct 63 ms 13804 KB Output is correct
27 Correct 1 ms 212 KB Output is correct
28 Correct 1 ms 212 KB Output is correct
29 Correct 1 ms 340 KB Output is correct
30 Correct 10 ms 340 KB Output is correct
31 Correct 47 ms 708 KB Output is correct
32 Correct 0 ms 212 KB Output is correct
33 Correct 1 ms 596 KB Output is correct
34 Correct 1 ms 596 KB Output is correct
35 Correct 2 ms 596 KB Output is correct
36 Correct 16 ms 764 KB Output is correct
37 Correct 69 ms 940 KB Output is correct
38 Correct 4 ms 3152 KB Output is correct
39 Correct 4 ms 3152 KB Output is correct
40 Correct 6 ms 3152 KB Output is correct
41 Correct 22 ms 3152 KB Output is correct
42 Correct 94 ms 3576 KB Output is correct
43 Correct 78 ms 56804 KB Output is correct
44 Correct 79 ms 56804 KB Output is correct
45 Correct 100 ms 56744 KB Output is correct
46 Correct 109 ms 56756 KB Output is correct
47 Correct 201 ms 56780 KB Output is correct
48 Correct 6 ms 2132 KB Output is correct
49 Correct 37 ms 2260 KB Output is correct
50 Correct 162 ms 2416 KB Output is correct
51 Correct 333 ms 2784 KB Output is correct
52 Correct 44 ms 25640 KB Output is correct
53 Correct 99 ms 25684 KB Output is correct
54 Correct 372 ms 25840 KB Output is correct
55 Correct 675 ms 26332 KB Output is correct
56 Correct 228 ms 146836 KB Output is correct
57 Correct 357 ms 146912 KB Output is correct
58 Correct 915 ms 147136 KB Output is correct
59 Correct 1500 ms 147464 KB Output is correct
60 Correct 493 ms 309920 KB Output is correct
61 Correct 623 ms 309984 KB Output is correct
62 Correct 1251 ms 310340 KB Output is correct
63 Correct 2098 ms 310640 KB Output is correct
64 Correct 3750 ms 310552 KB Output is correct
65 Correct 2880 ms 245740 KB Output is correct
66 Correct 3091 ms 252528 KB Output is correct
67 Correct 2962 ms 250676 KB Output is correct
68 Correct 3034 ms 253172 KB Output is correct
69 Correct 2972 ms 236576 KB Output is correct
70 Correct 2573 ms 158100 KB Output is correct
71 Correct 4280 ms 312408 KB Output is correct
72 Correct 4033 ms 312364 KB Output is correct
73 Correct 4083 ms 312476 KB Output is correct
74 Correct 4100 ms 310856 KB Output is correct
75 Correct 4013 ms 292144 KB Output is correct
76 Correct 3493 ms 190204 KB Output is correct
77 Correct 4463 ms 345184 KB Output is correct
78 Correct 4387 ms 345196 KB Output is correct
79 Correct 4417 ms 345488 KB Output is correct
80 Correct 4372 ms 343372 KB Output is correct
81 Correct 4214 ms 321008 KB Output is correct
82 Correct 3697 ms 202432 KB Output is correct
83 Correct 4455 ms 345384 KB Output is correct
84 Correct 4299 ms 345280 KB Output is correct
85 Correct 4728 ms 349348 KB Output is correct
86 Correct 4576 ms 347492 KB Output is correct
87 Correct 4473 ms 325204 KB Output is correct
88 Correct 3904 ms 206584 KB Output is correct
89 Correct 3037 ms 252912 KB Output is correct
90 Correct 3471 ms 277760 KB Output is correct
91 Correct 4054 ms 307520 KB Output is correct
92 Correct 4164 ms 315728 KB Output is correct
93 Correct 4342 ms 326872 KB Output is correct
94 Correct 4338 ms 334708 KB Output is correct
95 Correct 4342 ms 348120 KB Output is correct
96 Correct 4475 ms 348064 KB Output is correct
97 Correct 4436 ms 347984 KB Output is correct
98 Correct 4309 ms 348524 KB Output is correct
99 Correct 4325 ms 347992 KB Output is correct
100 Correct 4438 ms 348104 KB Output is correct