#include <bits/stdc++.h>
using namespace std;
#define bug(x) cout << #x << " " << x << endl
#define pii pair<int, int>
const int maxn = 5e5 + 10;
vector<int> adj[maxn], dist( maxn, maxn ), grau( maxn ), nivel( maxn );
vector<bool> sheep( maxn ), marc( maxn );
set<pair<int, int>> folhas;
queue<int> fila;
void add( int x, int d ){ fila.push(x); dist[x] = d; }
void bfs( vector<int>& sources ){
for( int x : sources ) add( x, 0 );
while( !fila.empty() ){
int cur = fila.front(); fila.pop();
for( int viz : adj[cur] ) if( dist[viz] > dist[cur] + 1 ) add( viz, dist[cur] + 1 );
}
}
int get_centro( int n ){
queue<int> fila;
for( int i = 1; i <= n; i++ ) if( grau[i] == 1 ) fila.push(i);
while( !fila.empty() ){
int cur = fila.front(); fila.pop();
if( grau[cur] == 0 ){
for( int i = 1; i <= n; i++ ) grau[i] = adj[i].size();
return cur;
}
for( int viz : adj[cur] ) if( --grau[viz] == 1 ) fila.push(viz);
}
}
void dfsInit( int cur, int pai ){
for( int viz : adj[cur] ) if( viz != pai ){ nivel[viz] = nivel[cur] + 1; dfsInit( viz, cur ); }
if( !sheep[cur] ) nivel[cur] = maxn;
if( grau[cur] == 1 ) folhas.insert({ nivel[cur], cur });
}
int get_next( int node ){ for( int viz : adj[node] ) if( !marc[viz] ) return viz; }
int get_pastor( int cur, int pai ){
for( int viz : adj[cur] ) if( !marc[viz] && viz != pai && dist[viz] > dist[cur] ) return get_pastor( viz, cur );
return cur;
}
void dfs( int cur ){
marc[cur] = true;
for( int viz : adj[cur] ) if( !marc[viz] && dist[viz] < dist[cur] ) dfs( viz );
}
int main(){
int n, k; cin >> n >> k;
if( n == 1 ){ cout << 1 << endl << 1; return 0; }
for( int i = 1; i < n; i++ ){
int a, b; cin >> a >> b;
adj[a].push_back(b); grau[a]++;
adj[b].push_back(a); grau[b]++;
}
vector<int> v(n), resp;
for( int i = 0; i < n; i++ ){ cin >> v[i]; sheep[v[i]] = true; }
bfs(v);
int centro = get_centro(n);
dfsInit( centro, centro );
while( !folhas.empty() ){
int cur = prev(folhas.end())->second; folhas.erase(prev(folhas.end()));
if( !sheep[cur] ) marc[cur] = true;
if( marc[cur] ) continue;
int pastor = get_pastor(cur, cur), next = get_next(cur);
resp.push_back(pastor);
if( --grau[next] == 1 ) folhas.insert({ nivel[next], next });
dfs(pastor);
}
sort( resp.begin(), resp.end() );
cout << resp.size() << endl;
for( int x : resp ) cout << x << " "; cout << endl;
}
Compilation message
pastiri.cpp: In function 'int main()':
pastiri.cpp:82:3: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
82 | for( int x : resp ) cout << x << " "; cout << endl;
| ^~~
pastiri.cpp:82:41: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
82 | for( int x : resp ) cout << x << " "; cout << endl;
| ^~~~
pastiri.cpp: In function 'int get_centro(int)':
pastiri.cpp:23:14: warning: control reaches end of non-void function [-Wreturn-type]
23 | queue<int> fila;
| ^~~~
pastiri.cpp: In function 'int get_next(int)':
pastiri.cpp:41:83: warning: control reaches end of non-void function [-Wreturn-type]
41 | int get_next( int node ){ for( int viz : adj[node] ) if( !marc[viz] ) return viz; }
| ^
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
219 ms |
63824 KB |
Integer 0 violates the range [1, 500000] |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
9 ms |
18520 KB |
Sheep 857 not protected |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
7 ms |
18268 KB |
Sheep 16 not protected |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
470 ms |
51636 KB |
Sheep 216 not protected |
2 |
Halted |
0 ms |
0 KB |
- |