#include <bits/stdc++.h>
using namespace std;
#define int ll
#define FOR(i,s,e) for(ll i = s; i <= (ll)e; ++i)
#define DEC(i,s,e) for(ll i = s; i >= (ll)e; --i)
#define IAMSPEED ios_base::sync_with_stdio(false); cin.tie(0);
#ifdef LOCAL
#define db(x) cerr << #x << "=" << x << "\n"
#define db2(x, y) cerr << #x << "=" << x << " , " << #y << "=" << y << "\n"
#define db3(a,b,c) cerr<<#a<<"="<<a<<","<<#b<<"="<<b<<","<<#c<<"="<<c<<"\n"
#define dbv(v) cerr << #v << ":"; for (auto ite : v) cerr << ite << ' '; cerr <<"\n"
#define dbvp(v) cerr << #v << ":"; for (auto ite : v) cerr << "{" << ite.f << ',' << ite.s << "} "; cerr << "\n"
#define dba(a,ss,ee) cerr << #a << ":"; FOR(ite,ss,ee) cerr << a[ite] << ' '; cerr << "\n"
#else
#define db(x)
#define db2(x,y)
#define db3(a,b,c)
#define dbv(v)
#define dbvp(v)
#define dba(a,ss,ee)
#endif
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define ll long long
#define pb push_back
#define eb emplace_back
#define all(x) (x).begin(), (x).end()
#define f first
#define s second
#define g0(x) get<0>(x)
#define g1(x) get<1>(x)
#define g2(x) get<2>(x)
#define g3(x) get<3>(x)
#define reach cerr << "LINE: " << __LINE__ << "\n";
typedef pair <ll, ll> pi;
typedef tuple<ll,ll,ll> ti3;
typedef tuple<ll,ll,ll,ll> ti4;
ll rand(ll a, ll b) { return a + rng() % (b-a+1); }
const int MOD = 1e9 + 7;
const int inf = (int)1e9 + 500;
const long long oo = (ll)1e18 + 500;
template <typename T> bool chmax(T& a, const T b) { return a<b ? a = b, 1 : 0; }
template <typename T> bool chmin(T& a, const T b) { return a>b ? a = b, 1 : 0; }
const int MAXN = 500005;
int n,k;
vector<int> V[MAXN];
int dist[MAXN]; // dist to nearest sheep
bool done[MAXN];
int depth[MAXN];
int dd[MAXN];
int twok[MAXN][20];
void dfs(int x, int p) {
twok[x][0]=p;
FOR(i,1,19) {
if(twok[x][i-1]==-1)break;
twok[x][i]=twok[twok[x][i-1]][i-1];
}
for(auto v:V[x])if(v^p) {
depth[v]=depth[x]+1;
dfs(v,x);
}
}
int32_t main()
{
IAMSPEED
memset(twok,-1,sizeof twok);
cin >> n >> k;
queue<int> q;
vector<int> sheep;
FOR(i,1,n-1) {
int a,b; cin >> a >> b;
V[a].pb(b);
V[b].pb(a);
}
FOR(i,1,k) {
int x; cin >> x;
sheep.pb(x);
}
FOR(i,0,MAXN-1)dist[i]=oo;
for(auto i:sheep){
q.push(i);
dist[i]=0;
}
map<int,vector<int>> mp;
int pre=0;
vector<int> out;
vector<int> push;
int curdist=0;
while(q.size()) {
int x=q.front(); q.pop();
for(auto v:V[x]){
if(dist[v] == oo){
dist[v]=dist[x]+1;
q.push(v);
}
}
}
dfs(1,-1);
sort(all(sheep), [](int a, int b) {
return depth[a] > depth[b];
});
FOR(i,0,MAXN-1)dd[i]=oo;
dba(dist,1,n);
dba(depth,1,n);
for(auto sh:sheep) {
//db(sh);
dba(done,1,n);
if(done[sh])continue;
int cur=sh;
DEC(i,20,0) {
if(twok[cur][i] == -1)continue;
if(dist[twok[cur][i]] != (depth[sh] - depth[twok[cur][i]]))continue;
cur=twok[cur][i]; // lift it there.
}
//put a shephard at cur.
db2(sh,cur);
q.push(cur);
dd[cur]=0;
out.pb(cur);
int finaldist=dist[cur];
while(q.size()) {
int x=q.front(); q.pop();
done[cur]=1;
if(dd[x]==finaldist)continue;
for(auto v:V[x]) {
if(dd[v]==oo || dd[v] > dd[x]+1) {
done[v]=1;
q.push(v);
dd[v]=dd[x]+1;
}
}
}
}
cout << out.size() << '\n';
for(auto i:out)cout<<i<<' ';
}
Compilation message
pastiri.cpp: In function 'int32_t main()':
pastiri.cpp:86:6: warning: unused variable 'pre' [-Wunused-variable]
86 | int pre=0;
| ^~~
pastiri.cpp:89:6: warning: unused variable 'curdist' [-Wunused-variable]
89 | int curdist=0;
| ^~~~~~~
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
282 ms |
147872 KB |
Output is correct |
| 2 |
Correct |
338 ms |
148336 KB |
Output is correct |
| 3 |
Correct |
317 ms |
148288 KB |
Output is correct |
| 4 |
Correct |
434 ms |
159024 KB |
Output is correct |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
41 ms |
98340 KB |
Sheep 3325 not protected |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
41 ms |
98224 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
676 ms |
128368 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
