#include<bits/stdc++.h>
#define taskname "sheep"
using namespace std;
const int N=5e5+1;
int n, k, a[N], dep[N], par[N], dist[N], del[N], vis[N];
set<int> g[N];
void bfs(){
memset(dist, -1, sizeof dist);
queue<int> q;
for (int i=1; i<=n; ++i) if (a[i]) q.push(i), dist[i]=0;
while (q.size()){
int u=q.front(); q.pop();
for (int v:g[u]) if (dist[v]==-1){
dist[v]=dist[u]+1;
q.push(v);
}
}
}
void dfs(int u, int p){
par[u]=p;
for (int v:g[u]) if (v!=p){
dep[v]=dep[u]+1;
dfs(v, u);
}
}
void bfs(int root){
queue<int> q;
vector<int> vv;
q.push(root); vis[root]=0;
vv.push_back(root);
while (q.size()){
int u=q.front(); q.pop();
if (vis[u]==dist[root]) continue;
for (int v:g[u]) if (vis[v]==-1){
vis[v]=vis[u]+1;
q.push(v);
vv.push_back(v);
}
}
for (int i:vv){
del[i]=1;
vis[i]=-1;
}
}
int32_t main(){
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
// freopen(taskname".inp", "r", stdin);
// freopen(taskname".out", "w", stdout);
cin >> n >> k;
for (int i=1; i<n; ++i){
int u, v; cin >> u >> v;
g[u].insert(v);
g[v].insert(u);
}
for (int i=1; i<=k; ++i){
int x; cin >> x;
a[x]=1;
}
bfs();
dfs(1, 0);
memset(vis, -1, sizeof vis);
vector<int> vv;
for (int i=1; i<=n; ++i) if (a[i]) vv.push_back(i);
sort(vv.begin(), vv.end(), [&](int x, int y){
return dep[x]<dep[y];
});
vector<int> ans;
while (vv.size()){
int u=vv.back(); vv.pop_back();
int v=u;
while (dist[par[v]]==dep[u]-dep[par[v]]) v=par[v];
ans.push_back(v);
bfs(v);
while (vv.size() && del[vv.back()]) vv.pop_back();
}
cout << ans.size() << '\n';
for (int i:ans) cout << i << ' ';
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
148 ms |
114392 KB |
Output is correct |
2 |
Correct |
184 ms |
113764 KB |
Output is correct |
3 |
Correct |
186 ms |
113764 KB |
Output is correct |
4 |
Correct |
237 ms |
118852 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
8 ms |
33880 KB |
Output is correct |
2 |
Correct |
8 ms |
33892 KB |
Output is correct |
3 |
Correct |
591 ms |
90044 KB |
Output is correct |
4 |
Correct |
611 ms |
90048 KB |
Output is correct |
5 |
Correct |
627 ms |
89948 KB |
Output is correct |
6 |
Execution timed out |
1045 ms |
95992 KB |
Time limit exceeded |
7 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
7 ms |
33624 KB |
Output is correct |
2 |
Correct |
7 ms |
33628 KB |
Output is correct |
3 |
Correct |
7 ms |
33456 KB |
Output is correct |
4 |
Correct |
7 ms |
33628 KB |
Output is correct |
5 |
Correct |
7 ms |
33628 KB |
Output is correct |
6 |
Correct |
7 ms |
33628 KB |
Output is correct |
7 |
Correct |
7 ms |
33456 KB |
Output is correct |
8 |
Correct |
7 ms |
33656 KB |
Output is correct |
9 |
Correct |
7 ms |
33656 KB |
Output is correct |
10 |
Correct |
7 ms |
33624 KB |
Output is correct |
11 |
Correct |
9 ms |
33624 KB |
Output is correct |
12 |
Correct |
7 ms |
33372 KB |
Output is correct |
13 |
Correct |
11 ms |
33880 KB |
Output is correct |
14 |
Correct |
7 ms |
33628 KB |
Output is correct |
15 |
Correct |
7 ms |
33624 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
596 ms |
83284 KB |
Output is correct |
2 |
Correct |
588 ms |
89936 KB |
Output is correct |
3 |
Correct |
668 ms |
92872 KB |
Output is correct |
4 |
Correct |
607 ms |
89212 KB |
Output is correct |
5 |
Correct |
556 ms |
81736 KB |
Output is correct |
6 |
Correct |
745 ms |
96732 KB |
Output is correct |
7 |
Correct |
785 ms |
95000 KB |
Output is correct |
8 |
Correct |
821 ms |
94904 KB |
Output is correct |
9 |
Execution timed out |
1066 ms |
93312 KB |
Time limit exceeded |
10 |
Halted |
0 ms |
0 KB |
- |