답안 #828365

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
828365 2023-08-17T08:56:30 Z serifefedartar Cat in a tree (BOI17_catinatree) C++17
51 / 100
1000 ms 31920 KB
#include <bits/stdc++.h>
using namespace std;
 
#define fast ios::sync_with_stdio(0);cin.tie(0);
typedef long long ll;
#define f first
#define s second
#define MOD 998244353
#define LOGN 18
#define MAXN 200005

vector<vector<int>> graph;
vector<int> par, sz, nearest;
int up[LOGN][MAXN], depth[MAXN];
bool marked[MAXN];

void dfs(int node, int parent) {
	for (auto u : graph[node]) {
		if (u == parent)
			continue;
		depth[u] = depth[node] + 1;
		up[0][u] = node;
		for (int i = 1; i < LOGN; i++)
			up[i][u] = up[i-1][up[i-1][u]];
		dfs(u, node);
	}
}

int find(int node, int k) {
	for (int i = 0; i < LOGN; i++) {
		if ((1<<i) & k)
			node = up[i][node];
	}
	return node;
}

int lca(int a, int b) {
	if (depth[b] > depth[a])
		swap(a, b);
	a = find(a, depth[a] - depth[b]);
	if (a == b)
		return a;
	for (int i = LOGN-1; i >= 0; i--) {
		if (up[i][a] != up[i][b]) {
			a = up[i][a];
			b = up[i][b];
		}
	}
	return up[0][a];
}

int dist(int a, int b) {
	return depth[a] + depth[b] - 2*depth[lca(a, b)];
}
	
int get_sz(int node, int parent) {
	for (auto u : graph[node]) {
		if (u == parent || marked[u])
			continue;
		sz[node] += get_sz(u, node);
	}
	return sz[node];
}

int find_centro(int node, int parent, int n) {
	for (auto u : graph[node]) {
		if (u == parent || marked[u])
			continue;
		if (sz[u] * 2 > n)
			return find_centro(u, node, n);
	}
	return node;
}

void decompose(int node, int parent) {
	int n = get_sz(node, parent);
	int centro = find_centro(node, node, n);

	par[centro] = parent;
	marked[centro] = true;
	for (auto u : graph[centro]) {
		if (!marked[u] && u != parent)
			decompose(u, centro);
	}
}

int main() {
	int N, D;
	cin >> N >> D;

	graph = vector<vector<int>>(N, vector<int>());
	nearest = vector<int>(N, 1e9);
	par = vector<int>(N, -1);
	sz = vector<int>(N, 1);
	for (int i = 1; i < N; i++) {
		int x; cin >> x;
		graph[x].push_back(i);
		graph[i].push_back(x);
	}
	for (int i = 0; i < LOGN; i++)
		up[i][0] = 0;
	dfs(0, 0);
	decompose(0, -1);

	vector<pair<int,int>> order;
	for (int i = 0; i < N; i++)
		order.push_back({depth[i], i});
	sort(order.rbegin(), order.rend());

	int ans = 0;
	for (auto u : order) {
		int node = u.s;
		int now = node;
		int mn_dist = 1e9;
		while (now != -1) {
			mn_dist = min(mn_dist, dist(node, now) + nearest[now]);
			now = par[now];
		}

		if (mn_dist >= D) {
			ans++;
			int now = node;
			while (now != -1) {
				nearest[now] = min(nearest[now], dist(node, now));
				now = par[now];
			}
		}
	}
	cout << ans << "\n";
}
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 0 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 0 ms 340 KB Output is correct
10 Correct 1 ms 340 KB Output is correct
11 Correct 0 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 0 ms 340 KB Output is correct
15 Correct 0 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 0 ms 340 KB Output is correct
19 Correct 0 ms 340 KB Output is correct
20 Correct 1 ms 340 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 0 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 0 ms 340 KB Output is correct
10 Correct 1 ms 340 KB Output is correct
11 Correct 0 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 0 ms 340 KB Output is correct
15 Correct 0 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 0 ms 340 KB Output is correct
19 Correct 0 ms 340 KB Output is correct
20 Correct 1 ms 340 KB Output is correct
21 Correct 4 ms 652 KB Output is correct
22 Correct 1 ms 468 KB Output is correct
23 Correct 1 ms 468 KB Output is correct
24 Correct 1 ms 468 KB Output is correct
25 Correct 2 ms 468 KB Output is correct
26 Correct 1 ms 468 KB Output is correct
27 Correct 2 ms 468 KB Output is correct
28 Correct 2 ms 596 KB Output is correct
29 Correct 2 ms 596 KB Output is correct
30 Correct 2 ms 596 KB Output is correct
31 Correct 2 ms 596 KB Output is correct
32 Correct 1 ms 596 KB Output is correct
33 Correct 2 ms 596 KB Output is correct
34 Correct 2 ms 596 KB Output is correct
35 Correct 2 ms 596 KB Output is correct
36 Correct 2 ms 596 KB Output is correct
37 Correct 1 ms 596 KB Output is correct
38 Correct 2 ms 596 KB Output is correct
39 Correct 3 ms 596 KB Output is correct
40 Correct 4 ms 724 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 0 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 0 ms 340 KB Output is correct
10 Correct 1 ms 340 KB Output is correct
11 Correct 0 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 0 ms 340 KB Output is correct
15 Correct 0 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 0 ms 340 KB Output is correct
19 Correct 0 ms 340 KB Output is correct
20 Correct 1 ms 340 KB Output is correct
21 Correct 4 ms 652 KB Output is correct
22 Correct 1 ms 468 KB Output is correct
23 Correct 1 ms 468 KB Output is correct
24 Correct 1 ms 468 KB Output is correct
25 Correct 2 ms 468 KB Output is correct
26 Correct 1 ms 468 KB Output is correct
27 Correct 2 ms 468 KB Output is correct
28 Correct 2 ms 596 KB Output is correct
29 Correct 2 ms 596 KB Output is correct
30 Correct 2 ms 596 KB Output is correct
31 Correct 2 ms 596 KB Output is correct
32 Correct 1 ms 596 KB Output is correct
33 Correct 2 ms 596 KB Output is correct
34 Correct 2 ms 596 KB Output is correct
35 Correct 2 ms 596 KB Output is correct
36 Correct 2 ms 596 KB Output is correct
37 Correct 1 ms 596 KB Output is correct
38 Correct 2 ms 596 KB Output is correct
39 Correct 3 ms 596 KB Output is correct
40 Correct 4 ms 724 KB Output is correct
41 Correct 146 ms 29804 KB Output is correct
42 Correct 140 ms 15764 KB Output is correct
43 Correct 122 ms 15824 KB Output is correct
44 Correct 113 ms 15832 KB Output is correct
45 Correct 111 ms 15816 KB Output is correct
46 Correct 342 ms 31000 KB Output is correct
47 Correct 283 ms 30964 KB Output is correct
48 Correct 285 ms 31052 KB Output is correct
49 Correct 321 ms 31032 KB Output is correct
50 Correct 80 ms 16256 KB Output is correct
51 Correct 93 ms 16268 KB Output is correct
52 Correct 75 ms 16280 KB Output is correct
53 Correct 197 ms 31832 KB Output is correct
54 Correct 198 ms 31920 KB Output is correct
55 Correct 205 ms 31896 KB Output is correct
56 Correct 8 ms 852 KB Output is correct
57 Correct 601 ms 5260 KB Output is correct
58 Execution timed out 1089 ms 21640 KB Time limit exceeded
59 Halted 0 ms 0 KB -