#include<bits/stdc++.h>
#define all(s) s.begin(),s.end()
using namespace std;
typedef int ll;
typedef pair<ll,ll>pll;
ll n,x,y,k,d[500009],a[500009],h[500009],c,pp[500009];
pll op[500009];
vector<vector<ll> >v;
queue<pll>q;
vector<ll>ans;
bool b[500009];
void dfs(ll u,ll p)
{
h[u]=h[p]+1;
for(auto z:v[u])
if(z!=p)
dfs(z,u);
}
bool cmp(ll xo,ll yo)
{
if(h[xo]==h[yo])
return x<y;
return h[xo]>h[yo];
}
struct node
{
ll f,s,t;
};
queue<node>dq;
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
scanf("%d%d",&n,&k);
v.resize(n+1);
for(ll i=1; i<n; i++)
{
scanf("%d%d",&x,&y);
v[x].push_back(y);
v[y].push_back(x);
}
for(ll i=1; i<=n; i++)
d[i]=1e9,op[i]= {1e9,1e9};
for(ll i=1; i<=k; i++)
scanf("%d",&a[i]),d[a[i]]=0,q.push({a[i],a[i]});
dfs(1,0);
while(!q.empty())
{
x=q.front().first;
y=q.front().second;
q.pop();
op[y]=min(op[y], {h[x],x});
if(pp[x]!=y)
continue;
for(auto z:v[x])
{
if(d[z]<d[x]+1)
continue;
if(d[z]==d[x]+1)
{
if(h[pp[z]]>h[x])
continue;
if(pp[z]<x)
continue;
}
pp[z]=x;
d[z]=d[x]+1;
q.push({z,y});
}
}
sort(a+1,a+k+1,cmp);
for(ll i=1; i<=k; i++)
{
if(b[a[i]])
continue;
ans.push_back(op[a[i]].second);
dq.push({op[a[i]].second,h[a[i]]-op[a[i]].first,0});
while(!dq.empty())
{
x=dq.front().f;
c=dq.front().s;
ll p=dq.front().t;
dq.pop();
b[x]=1;
if(c==0)
continue;
for(auto z:v[x])
if(z!=p)
dq.push({z,c-1,x});
}
}
cout<<ans.size()<<endl;
for(auto z:ans)
cout<<z<<" ";
return 0;
}
Compilation message
pastiri.cpp: In function 'int main()':
pastiri.cpp:35:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
35 | scanf("%d%d",&n,&k);
| ~~~~~^~~~~~~~~~~~~~
pastiri.cpp:39:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
39 | scanf("%d%d",&x,&y);
| ~~~~~^~~~~~~~~~~~~~
pastiri.cpp:46:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
46 | scanf("%d",&a[i]),d[a[i]]=0,q.push({a[i],a[i]});
| ~~~~~^~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
197 ms |
59060 KB |
Output is correct |
| 2 |
Incorrect |
197 ms |
59716 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
716 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
460 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
457 ms |
36996 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
