Submission #1066225

#	Time	Username	Problem	Language	Result	Execution time	Memory
1066225		epicci23	Keys (IOI21_keys)	C++17	100 / 100	964 ms	125076 KiB

keys

#include "bits/stdc++.h"
#define all(v) v.begin() , v.end()
#define sz(a) (int)a.size()
using namespace std;

const int N = 3e5 + 5;
vector<int> v[N],comp[N];
set<array<int,2>> adj[N];
set<int> s[N];
int vis[N],mark[N];
vector<int> cur,par(N,0);

void merge_info(int a,int b){
  a=par[a],b=par[b];
  if(a==b) return;
  if(sz(comp[a])+sz(s[a])+sz(adj[a])+sz(v[a])
    <sz(comp[b])+sz(s[b])+sz(adj[b])+sz(v[b])) swap(a,b);
  mark[a]&=mark[b];
  for(int x:v[b]) v[a].push_back(x);
  for(int x:comp[b]){
    comp[a].push_back(x);
    par[x]=a;
  }  
  for(array<int,2> x:adj[b]){
    if(s[a].count(x[0])) v[a].push_back(x[1]);
    else adj[a].insert(x);
  }
  for(int u:s[b]){
   if(s[a].count(u)) continue;
   s[a].insert(u);
   auto it=adj[a].lower_bound({u,0});
   while(it!=adj[a].end() && (*it)[0]==u){
    v[a].push_back((*it)[1]);
    adj[a].erase(*it);
    it=adj[a].lower_bound({u,0});
   }
  }
  adj[b].clear();
  v[b].clear();
  comp[b].clear();
  s[b].clear();
}

void dfs(int c){
  if(vis[c]==2) return;
  vis[c]=1;
  cur.push_back(c);
  while(!v[par[c]].empty()){
    int x=par[v[par[c]].back()];
    v[par[c]].pop_back();
    if(x==par[c])
    if(vis[x]==2 || !mark[x]){
      mark[par[c]]=0;
      continue;
    }
    if(vis[x]==1){
      while(!cur.empty() && par[cur.back()]!=par[x]){
        merge_info(cur.back(),x);
        cur.pop_back();
      }
    }
    else{
      dfs(x);
      if(par[c]!=par[x]) mark[par[c]]=0;
    }
  }
 if(!cur.empty() && cur.back()==c) cur.pop_back();
 vis[c]=2;
}

vector<int> find_reachable(vector<int> R, vector<int> U, vector<int> V, vector<int> C){
  int n=sz(R),m=sz(U);
  iota(all(par),0);
  for(int i=0;i<n;i++){
    mark[i]=1;
    comp[i].push_back(i);
    s[i].insert(R[i]);
  } 
  for(int i=0;i<m;i++){
    int a=U[i],b=V[i],c=C[i];
    if(s[a].count(c)) v[a].push_back(b);
    else adj[a].insert({c,b});
    if(s[b].count(c)) v[b].push_back(a);
    else adj[b].insert({c,a});
  }
  for(int i=0;i<n;i++) if(!vis[i]) dfs(i);
  int mini=100000007;
  for(int i=0;i<n;i++) if(mark[par[i]]) mini=min(mini,sz(comp[par[i]]));
  vector<int> ans(n,0);
  for(int i=0;i<n;i++) if(mark[par[i]] && sz(comp[par[i]])==mini) ans[i]=1;
  return ans;
}

• Subtask 1: 9 / 9
• Subtask 2: 11 / 11
• Subtask 3: 17 / 17
• Subtask 4: 30 / 30
• Subtask 5: 33 / 33