oj.uz

답안 #727460

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
727460 2023-04-20T19:22:02 Z AdamGS Network (BOI15_net) C++17
100 / 100
 541 ms 68552 KB 
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
#define rep(a, b) for(int a = 0; a < (b); ++a)
#define st first
#define nd second
#define pb push_back
#define all(a) a.begin(), a.end()
const int LIM=5e5+7;
vector<int>V[LIM];
vector<pair<int,int>>T;
int tr[4*LIM], pre[LIM], post[LIM], jaki[LIM], lpre, N=1, ost=-1;
void DFS(int x, int o) {
  ++lpre;
  jaki[lpre]=x;
  pre[x]=lpre;
  for(auto i : V[x]) if(i!=o) DFS(i, x);
  post[x]=lpre;
}
void upd(int v) {
  v+=N;
  while(v) {
    --tr[v];
    v/=2;
  }
}
int cnt(int l, int r) {
  l+=N; r+=N;
  int ans=tr[l];
  if(l!=r) ans+=tr[r];
  while(l/2!=r/2) {
    if(l%2==0) ans+=tr[l+1];
    if(r%2==1) ans+=tr[r-1];
    l/=2; r/=2;
  }
  return ans;
}
int zejdz(int v) {
  if(v>=N) {
    upd(v-N);
    return jaki[v-N];
  }
  if(tr[2*v]>0) return zejdz(2*v);
  return zejdz(2*v+1);
}
int znajdz(int l, int r) {
  l+=N; r+=N;
  vector<int>A, B;
  A.pb(l);
  if(l!=r) B.pb(r);
  while(l/2!=r/2) {
    if(l%2==0) A.pb(l+1);
    if(r%2==1) B.pb(r-1);
    l/=2; r/=2;
  }
  for(auto i : A) if(tr[i]>0) return zejdz(i);
  reverse(all(B));
  for(auto i : B) if(tr[i]>0) return zejdz(i);
  return -1;
}
void DFS2(int x, int o, vector<int>&P) {
  int p=cnt(pre[x], post[x]);
  bool t=false;
  for(auto i : V[x]) if(i!=o) {
    int z=cnt(pre[i], post[i]);
    if(2*z>p+P.size()) t=true;
  }
  if(t) {
    int b=P.size();
    for(auto i : V[x]) if(i!=o && 2*cnt(pre[i], post[i])<=p+b) {
      int a=znajdz(pre[i], post[i]);
      while(a!=-1) {
        P.pb(a);
        a=znajdz(pre[i], post[i]);
      }
    }
    for(auto i : V[x]) if(i!=o && cnt(pre[i], post[i])) DFS2(i, x, P);
    return;
  }
  priority_queue<pair<ll,ll>>q;
  if(P.size()) q.push({P.size(), LIM});
  for(auto i : V[x]) if(i!=o && cnt(pre[i], post[i])) q.push({cnt(pre[i], post[i]), i});
  while(q.size()>1) {
    auto a=q.top(); q.pop();
    auto b=q.top(); q.pop();
    --a.st;
    if(a.st) q.push(a);
    --b.st;
    if(b.st) q.push(b);
    int r, t;
    if(a.nd==LIM) {
      r=P.back(); P.pop_back();
    } else r=znajdz(pre[a.nd], post[a.nd]);
    if(b.nd==LIM) {
      t=P.back();
      P.pop_back();
    } else t=znajdz(pre[b.nd], post[b.nd]);
    T.pb({r, t});
  }
  if(q.size()) {
    int p=q.top().nd, z;
    if(p==LIM) z=P.back();
    else z=znajdz(0, N-1);
    ost=z;
  }
}
int main() {
  ios_base::sync_with_stdio(0); cin.tie(0);
  int n;
  cin >> n;
  while(N<=n) N*=2;
  rep(i, n-1) {
    int a, b;
    cin >> a >> b; --a; --b;
    V[a].pb(b);
    V[b].pb(a);
  }
  int r=0;
  rep(i, n) if(V[i].size()>1) r=i;
  DFS(r, r);
  rep(i, n) if(V[i].size()==1) tr[N+pre[i]]=1;
  for(int i=N-1; i; --i) tr[i]=tr[2*i]+tr[2*i+1];
  vector<int>P;
  DFS2(r, r, P);
  if(ost!=-1) T.pb({ost, r});
  cout << T.size() << '\n';
  for(auto i : T) cout << i.st+1 << " " << i.nd+1 << '\n';
}

Compilation message

net.cpp: In function 'void DFS2(int, int, std::vector<int>&)':
net.cpp:67:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   67 |     if(2*z>p+P.size()) t=true;
      |        ~~~^~~~~~~~~~~

Subtask #1
18.0 / 18.0

# 결과 실행 시간 메모리 Grader output
1 Correct 7 ms 12028 KB Output is correct
2 Correct 7 ms 11988 KB Output is correct
3 Correct 7 ms 11988 KB Output is correct
4 Correct 6 ms 11988 KB Output is correct
5 Correct 7 ms 12068 KB Output is correct
6 Correct 6 ms 12072 KB Output is correct
7 Correct 7 ms 11988 KB Output is correct
8 Correct 6 ms 11988 KB Output is correct
9 Correct 7 ms 11988 KB Output is correct
10 Correct 7 ms 11988 KB Output is correct
11 Correct 7 ms 11988 KB Output is correct
12 Correct 7 ms 11988 KB Output is correct
13 Correct 6 ms 11988 KB Output is correct
14 Correct 6 ms 11988 KB Output is correct
15 Correct 7 ms 11988 KB Output is correct
16 Correct 7 ms 11988 KB Output is correct
17 Correct 7 ms 11988 KB Output is correct
18 Correct 7 ms 11988 KB Output is correct
19 Correct 7 ms 11988 KB Output is correct
20 Correct 6 ms 11988 KB Output is correct

Subtask #2
45.0 / 45.0

# 결과 실행 시간 메모리 Grader output
1 Correct 7 ms 12028 KB Output is correct
2 Correct 7 ms 11988 KB Output is correct
3 Correct 7 ms 11988 KB Output is correct
4 Correct 6 ms 11988 KB Output is correct
5 Correct 7 ms 12068 KB Output is correct
6 Correct 6 ms 12072 KB Output is correct
7 Correct 7 ms 11988 KB Output is correct
8 Correct 6 ms 11988 KB Output is correct
9 Correct 7 ms 11988 KB Output is correct
10 Correct 7 ms 11988 KB Output is correct
11 Correct 7 ms 11988 KB Output is correct
12 Correct 7 ms 11988 KB Output is correct
13 Correct 6 ms 11988 KB Output is correct
14 Correct 6 ms 11988 KB Output is correct
15 Correct 7 ms 11988 KB Output is correct
16 Correct 7 ms 11988 KB Output is correct
17 Correct 7 ms 11988 KB Output is correct
18 Correct 7 ms 11988 KB Output is correct
19 Correct 7 ms 11988 KB Output is correct
20 Correct 6 ms 11988 KB Output is correct
21 Correct 7 ms 12072 KB Output is correct
22 Correct 8 ms 12244 KB Output is correct
23 Correct 8 ms 12216 KB Output is correct
24 Correct 8 ms 12208 KB Output is correct
25 Correct 8 ms 12244 KB Output is correct
26 Correct 7 ms 12116 KB Output is correct
27 Correct 8 ms 12244 KB Output is correct
28 Correct 8 ms 12244 KB Output is correct
29 Correct 7 ms 12116 KB Output is correct
30 Correct 7 ms 12076 KB Output is correct
31 Correct 8 ms 12128 KB Output is correct
32 Correct 7 ms 12008 KB Output is correct
33 Correct 6 ms 12016 KB Output is correct
34 Correct 7 ms 12072 KB Output is correct
35 Correct 6 ms 11988 KB Output is correct
36 Correct 7 ms 11988 KB Output is correct
37 Correct 7 ms 12116 KB Output is correct
38 Correct 7 ms 12116 KB Output is correct
39 Correct 6 ms 11988 KB Output is correct
40 Correct 6 ms 11988 KB Output is correct
41 Correct 7 ms 11988 KB Output is correct
42 Correct 8 ms 12028 KB Output is correct
43 Correct 8 ms 12180 KB Output is correct
44 Correct 6 ms 11988 KB Output is correct
45 Correct 7 ms 12116 KB Output is correct
46 Correct 7 ms 12116 KB Output is correct
47 Correct 7 ms 11988 KB Output is correct
48 Correct 7 ms 12116 KB Output is correct
49 Correct 7 ms 12116 KB Output is correct
50 Correct 7 ms 12064 KB Output is correct
51 Correct 7 ms 11988 KB Output is correct
52 Correct 7 ms 12116 KB Output is correct
53 Correct 7 ms 12116 KB Output is correct
54 Correct 7 ms 12036 KB Output is correct
55 Correct 7 ms 12072 KB Output is correct
56 Correct 7 ms 12068 KB Output is correct
57 Correct 7 ms 12116 KB Output is correct
58 Correct 8 ms 12244 KB Output is correct

Subtask #3
37.0 / 37.0

# 결과 실행 시간 메모리 Grader output
1 Correct 7 ms 12028 KB Output is correct
2 Correct 7 ms 11988 KB Output is correct
3 Correct 7 ms 11988 KB Output is correct
4 Correct 6 ms 11988 KB Output is correct
5 Correct 7 ms 12068 KB Output is correct
6 Correct 6 ms 12072 KB Output is correct
7 Correct 7 ms 11988 KB Output is correct
8 Correct 6 ms 11988 KB Output is correct
9 Correct 7 ms 11988 KB Output is correct
10 Correct 7 ms 11988 KB Output is correct
11 Correct 7 ms 11988 KB Output is correct
12 Correct 7 ms 11988 KB Output is correct
13 Correct 6 ms 11988 KB Output is correct
14 Correct 6 ms 11988 KB Output is correct
15 Correct 7 ms 11988 KB Output is correct
16 Correct 7 ms 11988 KB Output is correct
17 Correct 7 ms 11988 KB Output is correct
18 Correct 7 ms 11988 KB Output is correct
19 Correct 7 ms 11988 KB Output is correct
20 Correct 6 ms 11988 KB Output is correct
21 Correct 7 ms 12072 KB Output is correct
22 Correct 8 ms 12244 KB Output is correct
23 Correct 8 ms 12216 KB Output is correct
24 Correct 8 ms 12208 KB Output is correct
25 Correct 8 ms 12244 KB Output is correct
26 Correct 7 ms 12116 KB Output is correct
27 Correct 8 ms 12244 KB Output is correct
28 Correct 8 ms 12244 KB Output is correct
29 Correct 7 ms 12116 KB Output is correct
30 Correct 7 ms 12076 KB Output is correct
31 Correct 8 ms 12128 KB Output is correct
32 Correct 7 ms 12008 KB Output is correct
33 Correct 6 ms 12016 KB Output is correct
34 Correct 7 ms 12072 KB Output is correct
35 Correct 6 ms 11988 KB Output is correct
36 Correct 7 ms 11988 KB Output is correct
37 Correct 7 ms 12116 KB Output is correct
38 Correct 7 ms 12116 KB Output is correct
39 Correct 6 ms 11988 KB Output is correct
40 Correct 6 ms 11988 KB Output is correct
41 Correct 7 ms 11988 KB Output is correct
42 Correct 8 ms 12028 KB Output is correct
43 Correct 8 ms 12180 KB Output is correct
44 Correct 6 ms 11988 KB Output is correct
45 Correct 7 ms 12116 KB Output is correct
46 Correct 7 ms 12116 KB Output is correct
47 Correct 7 ms 11988 KB Output is correct
48 Correct 7 ms 12116 KB Output is correct
49 Correct 7 ms 12116 KB Output is correct
50 Correct 7 ms 12064 KB Output is correct
51 Correct 7 ms 11988 KB Output is correct
52 Correct 7 ms 12116 KB Output is correct
53 Correct 7 ms 12116 KB Output is correct
54 Correct 7 ms 12036 KB Output is correct
55 Correct 7 ms 12072 KB Output is correct
56 Correct 7 ms 12068 KB Output is correct
57 Correct 7 ms 12116 KB Output is correct
58 Correct 8 ms 12244 KB Output is correct
59 Correct 431 ms 47488 KB Output is correct
60 Correct 541 ms 49248 KB Output is correct
61 Correct 6 ms 11988 KB Output is correct
62 Correct 7 ms 12000 KB Output is correct
63 Correct 373 ms 43176 KB Output is correct
64 Correct 9 ms 12476 KB Output is correct
65 Correct 17 ms 14332 KB Output is correct
66 Correct 141 ms 29248 KB Output is correct
67 Correct 434 ms 65696 KB Output is correct
68 Correct 497 ms 68552 KB Output is correct
69 Correct 16 ms 13400 KB Output is correct
70 Correct 128 ms 27428 KB Output is correct
71 Correct 474 ms 58140 KB Output is correct
72 Correct 462 ms 56540 KB Output is correct
73 Correct 103 ms 22584 KB Output is correct
74 Correct 473 ms 48032 KB Output is correct
75 Correct 43 ms 16584 KB Output is correct
76 Correct 461 ms 53884 KB Output is correct
77 Correct 377 ms 55108 KB Output is correct
78 Correct 32 ms 16556 KB Output is correct
79 Correct 441 ms 55772 KB Output is correct
80 Correct 10 ms 12372 KB Output is correct
81 Correct 138 ms 26392 KB Output is correct
82 Correct 461 ms 53568 KB Output is correct
83 Correct 466 ms 47980 KB Output is correct
84 Correct 459 ms 48008 KB Output is correct
85 Correct 481 ms 47728 KB Output is correct
86 Correct 498 ms 48968 KB Output is correct
87 Correct 506 ms 49240 KB Output is correct