#include <bits/stdc++.h>
using namespace std;
const int maxN = 5e5 + 5;
int depth[maxN], dis[maxN], par[20][maxN], done[maxN];
bool visited[maxN];
vector<int> adj[maxN];
vector<pair<int, int>> order;
void dfs(int u, int pre) {
for (auto v: adj[u]) {
if (v == pre) continue;
depth[v] = depth[u] + 1;
par[0][v] = u;
dfs(v, u);
}
}
void bfs() {
queue<int> Q;
for (auto it: order) {
visited[it.second] = true;
Q.push(it.second);
}
while (Q.size() > 0) {
int u = Q.front(); Q.pop();
for (auto v: adj[u]) {
if (visited[v]) continue;
visited[v] = true;
dis[v] = dis[u] + 1;
Q.push(u);
}
}
}
bool cmp(pair<int, int> A, pair<int, int> B) {
return A.first > B.first;
}
void mark_done(int u) {
done[u] = 1;
for (auto v: adj[u]) {
if (v == par[0][u] || done[v]) continue;
mark_done(v);
}
}
int main() {
ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
int n, k;
cin >> n >> k;
for (int i = 1; i < n; i++) {
int u, v;
cin >> u >> v;
adj[u].push_back(v);
adj[v].push_back(u);
}
depth[1] = 1;
dfs(1, 1);
for (int j = 1; j <= 18; j++)
for (int i = 1; i <= n; i++)
par[j][i] = par[j - 1][par[j - 1][i]];
for (int i = 1; i <= k; i++) {
int x;
cin >> x;
order.push_back({depth[x], x});
}
bfs();
sort(order.begin(), order.end(), cmp);
vector<int> ans;
for (auto it: order) {
int u = it.second;
if (done[u]) continue;
int x = u;
for (int j = 18; j >= 0; j--) {
int v = par[j][x];
if (v != 0 && depth[u] - depth[v] == dis[v]) x = v;
}
mark_done(x);
ans.push_back(x);
}
sort(ans.begin(), ans.end());
cout << ans.size() << '\n';
for (auto v: ans)
if (v != ans.back()) cout << v << ' ';
else cout << v;
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
136 ms |
106516 KB |
Output is correct |
2 |
Incorrect |
143 ms |
108888 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
7 ms |
12900 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
6 ms |
12384 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
366 ms |
78920 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |