제출 #524332

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
524332		keertan	Regions (IOI09_regions)	C++17	45 / 100	4037 ms	102004 KiB

regions

#include <bits/stdc++.h>
 
using namespace std;
//#define int  int64_t
#define rep(Begin,End) for (Begin=0;Begin<(End);Begin++)
#define all(x) x.begin(), x.end()
#define all1(x) x.rbegin(), x.rend()
#define sz(x) (int32_t)(x.size())
const int N = 3e5+4, mod =998244353;
const int64_t N1=1e18;
const double eps=1e-6,cmp=1e-3;
int tin[N],tout[N],c[N];
int tmr=1;
vector<int> adj[N];
vector<int> ctin[N],ctout[N],col[25001];
unordered_map<int,int> mp[25001];
int euler[N];
void dfs(int u){
  tin[u]=tmr;
  euler[tmr]=c[u];
  //cerr<<u<< " "<<c[u]<<"\n";
  ctin[c[u]].push_back(tmr++);
  col[c[u]].push_back(u);
  for (const int&  it:adj[u]){
    dfs(it);
  }
  tout[u]=tmr++;
  ctout[c[u]].push_back(tout[u]);
}
int child(int p,int chld){
  int ans=0;
  //cerr<<"chld";
  for (const int& it:col[chld]){
    //cerr<<it<<" ";
    int cur=0,cur1=0;
    for (int lg=(1ll<<18);lg;lg>>=1){
      if (sz(ctin[p])>=cur+lg && ctin[p][cur+lg-1]<tin[it]){
        cur+=lg;
      }
      if (sz(ctout[p])>=cur1+lg && ctout[p][cur1+lg-1]<=tin[it]){
        cur1+=lg;
      }
    }
    //cerr<<cur<<" "<<cur1;
    ans+=cur-cur1;
  }
  return ans;
}
int parent(int p,int chld){
  int ans=0;
  //cerr<<"gh";
  //cout<<tin[1]<<" "<<tout[1]<<"\n";
  for (const int& it:col[p]){
    ans+=upper_bound(all(ctin[chld]),tout[it])-ctin[chld].begin();
    ans-=upper_bound(all(ctin[chld]),tin[it])-ctin[chld].begin();
  }
  return ans;
}
void solve(){
  int n,r,q;
  cin>>n>>r>>q;
  vector<int>f(r+1);
  cin>>c[1];
  f[c[1]]++;
  for (int i=2,x,p;i<=n;i++){
    cin>>p>>x;
    c[i]=x;
    f[x]++;
    adj[p].push_back(i);
  }
  for (int i=0;i<=r;i++){
    ctin[i].reserve(f[i]+2);
    ctout[i].reserve(f[i]+2);
    col[i].reserve(f[i]+2);
  }
  dfs(1);
  
  for (int i=1;i<=r;i++){
    if (sz(col[i])>=512){
      vector<int> ok(tmr+1);
      for (const int& it:col[i]){
        ok[tin[it]]++;
        ok[tout[it]]--;
      }
      for (int j=1;j<tmr;j++){
        ok[j]+=ok[j-1];
        if (euler[j]){
          mp[euler[j]][i]+=ok[j]-!!(euler[j]==i);
        }
      }
    }
  }
  for (int r,r1;q;q--){
    cin>>r>>r1;
    if (sz(col[r])>=512){cout<<mp[r][r1]<<endl;continue;}
    else if (sz(col[r])<sz(col[r1])){
      cout<<parent(r,r1)<<endl;
    }
    else{
      cout<<child(r,r1)<<endl;
    }
  }
}
int32_t main(){
  ios::sync_with_stdio(false),cin.tie(nullptr),cout.tie(nullptr);
  int tq = 1;
  //cin>>tq;
  for (;tq;tq--){solve();}
}

• Subtask 1: 15 / 15
• Subtask 2: 30 / 85