oj.uz

Submission #855164

# Submission time Handle Problem Language Result Execution time Memory
855164 2023-09-30T11:18:22 Z mbfibat Dynamic Diameter (CEOI19_diameter) C++17
31 / 100
 5000 ms 376364 KB 
#include <bits/stdc++.h>

using namespace std;

#define int long long

typedef pair<int, int> ii;

const int N = 1e5 + 11;

vector<ii> adj[N];

bool is_c[N];

int totChild = 0;
int nChild[N];
int parCentroid[N];
void cal_child(int u, int p = 0) {
	nChild[u] = 1;
	for (auto [v, w] : adj[u])
		if (!is_c[v] && v != p) {
			cal_child(v, u);
			nChild[u] += nChild[v];
		}	
}
int find_c(int u, int p = 0) {
	for (auto [v, w] : adj[u])
		if (v != p && !is_c[v] && nChild[v] > totChild / 2)
			return find_c(v, u);
	return u;	
}

// --------------------------------------------

unordered_map<int, int> dist;

struct Node {
	int val = 0, lazy = 0;
	Node* l = nullptr, *r = nullptr;
	Node(){}
};

// each centroid root will have a segtree
Node* Seg[N];

void build(Node *cur, int l, int r) {
	if (l == r) {
		cur -> val = dist[l];
		return;
	}
	cur -> l = new Node();
	cur -> r = new Node();
	int mi = (l + r) / 2;
	build(cur -> l, l, mi);
	build(cur -> r, mi + 1, r);
	cur -> val = max(cur -> l -> val, cur -> r -> val);
}

void diffuse(Node *cur, int l, int r) {
	if (cur -> lazy) {
		cur -> val += cur -> lazy;
		if (l != r) {
			cur -> l -> lazy += cur -> lazy;
			cur -> r -> lazy += cur -> lazy;
		}
		cur -> lazy = 0;
	}
}

void upd(Node *cur, int l, int r, int L, int R, int val) {
	diffuse(cur, l, r);
//	cerr << "UPDATE: " << l << ' ' << r << ' ' << cur -> val << '\n';
	if (r < L || R < l) return;
	if (L <= l && r <= R) {
		cur -> lazy += val;
		diffuse(cur, l, r);
		return;
	}

	int mi = (l + r) / 2;
	upd(cur -> l, l, mi, L, R, val);
	upd(cur -> r, mi + 1, r, L, R, val);
	cur -> val = max(cur -> l -> val, cur -> r -> val);
}

int query(Node *cur, int l, int r, int L, int R) {
	diffuse(cur, l, r);
//	cerr << "QUERY: " << l << ' ' << r << ' ' << cur -> val << '\n';
	if (r < L || R < l) return 0;
	if (L <= l && r <= R) return cur -> val;

	int mi = (l + r) / 2;
	int val_l = query(cur -> l, l, mi, L, R);
	int val_r = query(cur -> r, mi + 1, r, L, R);
	return max(val_l, val_r);
}

int cur_root;
unordered_map<int, int> top;
map<ii, int> st, ed;

multiset<int> val_ms[N];
vector<ii> val_ord[N];

void dfs(int u, int d = 0, int p = 0) {
	st[ii(cur_root, u)] = ++top[cur_root];
	dist[top[cur_root]] = d;

//	cerr << "dist from cur_root to u: " << cur_root << ' ' << u << ' ' << d << " - with pos: " << top[cur_root] << '\n';

	for (auto [v, w] : adj[u]) {
		if (is_c[v] || v == p) continue;
		dfs(v, d + w, u);
	}
	ed[ii(cur_root, u)] = top[cur_root];
}

// get max of all paths throught u
int sol[N];
multiset<int> ans;

void prep(int root) {
	// for each centroid root, create a segment tree, using pointers to create this egment tree
	// store a multiset for each edge from root
	// using st[u] and ed[u] to get the range and know, when updating a subtree, we know what edge from root does that subtree belong

//	cerr << "root: " << root << '\n';

	// 1. create segtree: get all nodes that are !is_c[u]
	cur_root = root;

	Seg[root] = new Node();
	dist[root] = 0;
	dfs(root);
	build(Seg[root], 1, top[root]);


	// 2. store multiset for each edge
	for (auto [v, w] : adj[root]) {
		if (is_c[v]) continue;

		int l = st[ii(root, v)], r = ed[ii(root, v)];
		int val = query(Seg[root], 1, top[root], l, r);
//		cerr << "range get and query: " << l << ' ' << r << ' ' << val << '\n';

		val_ms[root].insert(val);
		val_ord[root].emplace_back(l, val);
	}
	sort(val_ord[root].begin(), val_ord[root].end());

	// offset for easier handling
	val_ms[root].insert(0); val_ms[root].insert(0);
	val_ord[root].emplace_back(top[root] + 1, 0);

	auto it = val_ms[root].rbegin();
	int v1 = *it; ++it; int v2 = *it;
	sol[root] = v1 + v2; ans.insert(sol[root]);
}

// --------------------------------------------

void centroid_decompose(int u, int p = 0) {
	cal_child(u); totChild = nChild[u];
	int c = find_c(u);

	parCentroid[c] = p;
	prep(c);

	is_c[c] = true;
	for (auto [v, w] : adj[c])
		if (!is_c[v])
			centroid_decompose(v, c);
}

void upd_edge(int root, int u1, int u2, int inc) {
//	cerr << '?' << root << ' ' << u1 << ' ' << u2 << ' ' << inc << '\n';
	// update on tree
//	for (auto [pos, v] : val_ord[root]) {
//		cerr << pos << ' ' << v << '\n';
//	}	
	int u = ((st[ii(root, u1)] > st[ii(root, u2)]) ? u1 : u2);
	upd(Seg[root], 1, top[root], st[ii(root, u)], ed[ii(root, u)], inc);
//	cerr << "range of subtree: " << st[ii(root, u)] << " " << ed[ii(root, u)] << '\n';

	int p = upper_bound(val_ord[root].begin(), val_ord[root].end(), ii(st[ii(root, u)], 2e18)) - val_ord[root].begin() - 1;
	int l = val_ord[root][p].first, r = val_ord[root][p + 1].first - 1;
//	cerr << "range of root edge: " << l << " " << r << '\n';

	int old_val = val_ord[root][p].second;
	int new_val = query(Seg[root], 1, top[root], l, r); 

//	cerr << "old val and new val: " << old_val << ' ' << new_val << '\n';
	val_ms[root].erase(val_ms[root].find(old_val));
	val_ms[root].insert(new_val);
	val_ord[root][p].second = new_val;

	auto it = val_ms[root].rbegin();
	int v1 = *it; ++it; int v2 = *it;
//	cerr << "two largest paths: " << v1 << ' ' << v2 << '\n';

	ans.erase(ans.find(sol[root]));
	sol[root] = v1 + v2; ans.insert(sol[root]);

	if (parCentroid[root])
		upd_edge(parCentroid[root], u1, u2, inc);
}

int32_t main() {
	ios::sync_with_stdio(false);
	cin.tie(0); cout.tie(0);

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

	vector<int> W(n);
	vector<ii> edges;
	for (int i = 0; i < n - 1; i++) {
		int u, v, c; cin >> u >> v >> c;

		W[i] = c;
		edges.emplace_back(u, v);

		adj[u].emplace_back(v, c);
		adj[v].emplace_back(u, c);
	}
	centroid_decompose(1);

	int last = 0;
	while (q--) {
		int d, e; cin >> d >> e;
		d = (d + last) % (n - 1);
		e = (e + last) % w;		

		int dif = e - W[d]; W[d] = e;

		auto [u, v] = edges[d];
		if (top[u] < top[v]) swap(u, v);
//		cerr << "dif: " << dif << '\n';
//		cerr << "set new value: " << e << '\n';
//		cerr << "u, v and top[u], top[v]: " << u << ' ' << v << ' ' << top[u] << ' ' << top[v] << '\n';		

		upd_edge(u, u, v, dif);

//		cerr << "all best paths: ";
//		for (int v : ans)
//			cerr << v << ' ';
//		cerr << '\n';
			
		last = *ans.rbegin();
		cout << last << '\n';
	}

}

Subtask #1
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12892 KB Output is correct
2 Correct 2 ms 12892 KB Output is correct
3 Correct 2 ms 12888 KB Output is correct
4 Correct 3 ms 12892 KB Output is correct
5 Correct 3 ms 12892 KB Output is correct
6 Correct 2 ms 12724 KB Output is correct
7 Correct 3 ms 12888 KB Output is correct
8 Correct 2 ms 12892 KB Output is correct
9 Correct 3 ms 12892 KB Output is correct
10 Correct 2 ms 12892 KB Output is correct
11 Correct 3 ms 12892 KB Output is correct
12 Correct 2 ms 12888 KB Output is correct
13 Correct 3 ms 12892 KB Output is correct
14 Correct 3 ms 12892 KB Output is correct
15 Correct 3 ms 12924 KB Output is correct
16 Correct 3 ms 12888 KB Output is correct
17 Correct 3 ms 12892 KB Output is correct
18 Correct 3 ms 12888 KB Output is correct

Subtask #2
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12892 KB Output is correct
2 Correct 2 ms 12892 KB Output is correct
3 Correct 2 ms 12888 KB Output is correct
4 Correct 3 ms 12892 KB Output is correct
5 Correct 3 ms 12892 KB Output is correct
6 Correct 2 ms 12724 KB Output is correct
7 Correct 3 ms 12888 KB Output is correct
8 Correct 2 ms 12892 KB Output is correct
9 Correct 3 ms 12892 KB Output is correct
10 Correct 2 ms 12892 KB Output is correct
11 Correct 3 ms 12892 KB Output is correct
12 Correct 2 ms 12888 KB Output is correct
13 Correct 3 ms 12892 KB Output is correct
14 Correct 3 ms 12892 KB Output is correct
15 Correct 3 ms 12924 KB Output is correct
16 Correct 3 ms 12888 KB Output is correct
17 Correct 3 ms 12892 KB Output is correct
18 Correct 3 ms 12888 KB Output is correct
19 Correct 31 ms 14428 KB Output is correct
20 Correct 34 ms 14936 KB Output is correct
21 Correct 41 ms 14940 KB Output is correct
22 Correct 48 ms 15380 KB Output is correct
23 Correct 69 ms 22100 KB Output is correct
24 Correct 93 ms 24664 KB Output is correct
25 Correct 106 ms 25804 KB Output is correct
26 Correct 125 ms 27560 KB Output is correct

Subtask #3
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12888 KB Output is correct
2 Correct 2 ms 12892 KB Output is correct
3 Correct 3 ms 12892 KB Output is correct
4 Correct 12 ms 13148 KB Output is correct
5 Correct 53 ms 13904 KB Output is correct
6 Correct 2 ms 12892 KB Output is correct
7 Correct 3 ms 13148 KB Output is correct
8 Correct 3 ms 13148 KB Output is correct
9 Correct 5 ms 13148 KB Output is correct
10 Correct 20 ms 13472 KB Output is correct
11 Correct 85 ms 14524 KB Output is correct
12 Correct 11 ms 16732 KB Output is correct
13 Correct 11 ms 16732 KB Output is correct
14 Correct 13 ms 16732 KB Output is correct
15 Correct 37 ms 17164 KB Output is correct
16 Correct 146 ms 18244 KB Output is correct
17 Correct 265 ms 92340 KB Output is correct
18 Correct 252 ms 92368 KB Output is correct
19 Correct 271 ms 92392 KB Output is correct
20 Correct 308 ms 92696 KB Output is correct
21 Correct 700 ms 93452 KB Output is correct

Subtask #4
0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 14940 KB Output is correct
2 Correct 48 ms 15172 KB Output is correct
3 Correct 211 ms 15680 KB Output is correct
4 Correct 413 ms 16360 KB Output is correct
5 Correct 98 ms 41424 KB Output is correct
6 Correct 191 ms 41768 KB Output is correct
7 Correct 649 ms 42584 KB Output is correct
8 Correct 1236 ms 43028 KB Output is correct
9 Correct 510 ms 182724 KB Output is correct
10 Correct 716 ms 183208 KB Output is correct
11 Correct 1735 ms 183508 KB Output is correct
12 Correct 3018 ms 184444 KB Output is correct
13 Correct 1051 ms 374496 KB Output is correct
14 Correct 1376 ms 374648 KB Output is correct
15 Correct 2675 ms 375336 KB Output is correct
16 Correct 4414 ms 376364 KB Output is correct
17 Execution timed out 5050 ms 375588 KB Time limit exceeded
18 Halted 0 ms 0 KB -

Subtask #5
0 / 24.0

# Verdict Execution time Memory Grader output
1 Execution timed out 5019 ms 290004 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #6
0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12892 KB Output is correct
2 Correct 2 ms 12892 KB Output is correct
3 Correct 2 ms 12888 KB Output is correct
4 Correct 3 ms 12892 KB Output is correct
5 Correct 3 ms 12892 KB Output is correct
6 Correct 2 ms 12724 KB Output is correct
7 Correct 3 ms 12888 KB Output is correct
8 Correct 2 ms 12892 KB Output is correct
9 Correct 3 ms 12892 KB Output is correct
10 Correct 2 ms 12892 KB Output is correct
11 Correct 3 ms 12892 KB Output is correct
12 Correct 2 ms 12888 KB Output is correct
13 Correct 3 ms 12892 KB Output is correct
14 Correct 3 ms 12892 KB Output is correct
15 Correct 3 ms 12924 KB Output is correct
16 Correct 3 ms 12888 KB Output is correct
17 Correct 3 ms 12892 KB Output is correct
18 Correct 3 ms 12888 KB Output is correct
19 Correct 31 ms 14428 KB Output is correct
20 Correct 34 ms 14936 KB Output is correct
21 Correct 41 ms 14940 KB Output is correct
22 Correct 48 ms 15380 KB Output is correct
23 Correct 69 ms 22100 KB Output is correct
24 Correct 93 ms 24664 KB Output is correct
25 Correct 106 ms 25804 KB Output is correct
26 Correct 125 ms 27560 KB Output is correct
27 Correct 2 ms 12888 KB Output is correct
28 Correct 2 ms 12892 KB Output is correct
29 Correct 3 ms 12892 KB Output is correct
30 Correct 12 ms 13148 KB Output is correct
31 Correct 53 ms 13904 KB Output is correct
32 Correct 2 ms 12892 KB Output is correct
33 Correct 3 ms 13148 KB Output is correct
34 Correct 3 ms 13148 KB Output is correct
35 Correct 5 ms 13148 KB Output is correct
36 Correct 20 ms 13472 KB Output is correct
37 Correct 85 ms 14524 KB Output is correct
38 Correct 11 ms 16732 KB Output is correct
39 Correct 11 ms 16732 KB Output is correct
40 Correct 13 ms 16732 KB Output is correct
41 Correct 37 ms 17164 KB Output is correct
42 Correct 146 ms 18244 KB Output is correct
43 Correct 265 ms 92340 KB Output is correct
44 Correct 252 ms 92368 KB Output is correct
45 Correct 271 ms 92392 KB Output is correct
46 Correct 308 ms 92696 KB Output is correct
47 Correct 700 ms 93452 KB Output is correct
48 Correct 11 ms 14940 KB Output is correct
49 Correct 48 ms 15172 KB Output is correct
50 Correct 211 ms 15680 KB Output is correct
51 Correct 413 ms 16360 KB Output is correct
52 Correct 98 ms 41424 KB Output is correct
53 Correct 191 ms 41768 KB Output is correct
54 Correct 649 ms 42584 KB Output is correct
55 Correct 1236 ms 43028 KB Output is correct
56 Correct 510 ms 182724 KB Output is correct
57 Correct 716 ms 183208 KB Output is correct
58 Correct 1735 ms 183508 KB Output is correct
59 Correct 3018 ms 184444 KB Output is correct
60 Correct 1051 ms 374496 KB Output is correct
61 Correct 1376 ms 374648 KB Output is correct
62 Correct 2675 ms 375336 KB Output is correct
63 Correct 4414 ms 376364 KB Output is correct
64 Execution timed out 5050 ms 375588 KB Time limit exceeded
65 Halted 0 ms 0 KB -