Submission #960514

#	Time	Username	Problem	Language	Result	Execution time	Memory
960514		Prieved1	Closing Time (IOI23_closing)	C++17	100 / 100	265 ms	43156 KiB

closing

#include "closing.h"
#include<bits/stdc++.h>
#include<vector>
#include<queue>
#include<cstring>
#include<set>
using namespace std;
const int MAXN=200010;
vector<pair<int,int>> g[MAXN];
long long distX[MAXN], distY[MAXN];
int dd[MAXN];
vector<int> path;
long long dist=0;
void dfsx(int at, int p) {
  for(auto [to,w]:g[at]) {
    if(to==p)continue;
    distX[to]=distX[at]+w;
    dfsx(to, at);
  }
}
void dfsy(int at, int p) {
  for(auto [to,w]:g[at]) {
    if(to==p)continue;
    distY[to]=distY[at]+w;
    dfsy(to, at);
    if(dd[to])dist+=w;
    dd[at]|=dd[to];
  }
  if(dd[at])path.push_back(at);
}
int max_score(int N, int X, int Y, long long K,
              std::vector<int> U, std::vector<int> V, std::vector<int> W)
{
  for(int i = 0;i<N-1;i++) {
    g[U[i]].push_back({V[i], W[i]});
    g[V[i]].push_back({U[i], W[i]});
  }
  dist=0;
  dd[X]=1;
  dfsx(X, -1);
  dfsy(Y, -1);
  int ans=0;
  // case 1
  {
    int cnt=0;
    priority_queue<long long> pq;
    for(int i = 0;i<N;i++) {
      pq.push(-distX[i]);
      pq.push(-distY[i]);
    }
    long long sum=0;
    while(sum<=K and pq.size()) {
      sum-=pq.top();
      cnt++;
      pq.pop();
      if(sum<=K)ans=max(ans,cnt);
    }
  }
  // case 2
  {
    for(int i = 0;i<N;i++) {
      if(distX[i]>distY[i])swap(distX[i], distY[i]);
      distY[i]-=distX[i];
    }
    int upd[N];
    memset(upd, 0, sizeof upd);
    long long sum=0;
    int cnt=0;
    priority_queue<long long> pq1;
    priority_queue<pair<long long,int>> pq2;
    multiset<long long> ms;
    for(int i:path) {
      sum+=distX[i];
      pq1.push(-distY[i]);
      cnt++;
      upd[i]++;
    }
    for(int i = 0;i<N;i++) {
      if(upd[i])continue;
      if(distX[i]>distY[i]) {
        pq2.push({-(distY[i]+distX[i]), i});
        ms.insert(distX[i]);
      }
      else {
        pq1.push(-distX[i]);
        pq1.push(-distY[i]);
      }
    }
    if(sum<=K)ans=max(ans, cnt);
    if(pq1.size() and sum-pq1.top()<=K)ans=max(ans, cnt+1);
    if(ms.size() and sum+(*ms.begin())<=K)ans=max(ans, cnt+1);
    if(pq1.size() and ms.size() and sum-pq1.top()+(*ms.begin())<=K)ans=max(ans, cnt+2);
    while(pq1.size() or pq2.size()) {
      if(pq1.size()>=2 and pq2.size()) {
        long long tmp=pq1.top();
        pq1.pop();
        if(-tmp-pq1.top()>=-pq2.top().first) {
          sum-=pq2.top().first;
          ms.erase(ms.find(distX[pq2.top().second]));
          cnt+=2;
          pq2.pop();
          pq1.push(tmp);
        }
        else {
          sum-=tmp;
          cnt++;
        }
      }
      else if(pq1.size()<=1 and pq2.size()) {
        sum-=pq2.top().first;
        ms.erase(ms.find(distX[pq2.top().second]));
        cnt+=2;
        pq2.pop();
      }
      else if(pq2.size()==0 and pq1.size()) {
        sum-=pq1.top();
        pq1.pop();
        cnt++;
      }
      if(sum<=K)ans=max(ans, cnt);
      if(pq1.size() and sum-pq1.top()<=K)ans=max(ans, cnt+1);
      if(ms.size() and sum+(*ms.begin())<=K)ans=max(ans, cnt+1);
      if(pq1.size() and ms.size() and sum-pq1.top()+(*ms.begin())<=K)ans=max(ans, cnt+2);
    }
  }
  for(int i = 0;i<=N;i++) {
    dd[i]=0;
    distX[i]=distY[i]=0;
    g[i].clear();
  }
  path.clear();
  return ans;
}

• Subtask 0: 0 / 0
• Subtask 1: 8 / 8
• Subtask 2: 9 / 9
• Subtask 3: 12 / 12
• Subtask 4: 14 / 14
• Subtask 5: 9 / 9
• Subtask 6: 11 / 11
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 17 / 17