제출 #435730

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
435730		DanerZein	분수 공원 (IOI21_parks)	C++17	15 / 100	359 ms	48644 KiB

parks

#include "parks.h"
#include <bits/stdc++.h>
using namespace std;
typedef pair<int,int> ii;
typedef vector<ii> vi;
const int MAX_N=2e5+10;
vector<vi> ox(MAX_N),oy(MAX_N);
int pa[MAX_N],tam[MAX_N];
void init(int n){
  for(int i=0;i<n;i++){
    pa[i]=i; tam[i]=1;
  }
}
int findset(int i){
  if(pa[i]==i) return i;
  return pa[i]=findset(pa[i]);
}
bool issameset(int i,int j){
  return findset(i)==findset(j);
}
void unionset(int i,int j){
  if(!issameset(i,j)){
    int u=findset(i),v=findset(j);
    pa[u]=v;
    tam[v]+=tam[u];
  }
}
int construct_roads(std::vector<int> x, std::vector<int> y) {
  int n=x.size();
  for(int i=0;i<n;i++){
    ox[x[i]].push_back(ii(y[i],i));
    oy[y[i]].push_back(ii(x[i],i));
  }
  for(int i=0;i<MAX_N;i++){
    sort(ox[i].begin(),ox[i].end());
    sort(oy[i].begin(),oy[i].end());
  }
  vector<int> ru,rv,ra,rb;
  set<ii> ba;
  init(n);
  for(int i=2;i<MAX_N;i+=2){
    int t=oy[i].size();
    for(int j=0;j<t-1;j++){
      int xi=oy[i][j].first,xj=oy[i][j+1].first;
      int u=oy[i][j].second,v=oy[i][j+1].second;
      if(xj-xi==2 && !issameset(u,v)){
	ru.push_back(oy[i][j].second);
	rv.push_back(oy[i][j+1].second);
	unionset(u,v);
	int xk=oy[i][j+2].first;
	auto it=lower_bound(oy[i-2].begin(),oy[i-2].end(),ii(xj,-1));
	if(j+2<t && oy[i][j+2].first-xj==2 && it!=oy[i-2].end() && (*it).first==xj){
	  ra.push_back(xi+1); rb.push_back(i+1);
	  ba.insert(ii(xi+1,i+1));
	  it=lower_bound(oy[i+2].begin(),oy[i+2].end(),ii(xi,-1));
	  int id=it-oy[i+2].begin();
	  if(it!=oy[i+2].end() && (*it).first==xi && id-1>=0 && oy[i+2][id].first-oy[i+2][id-1].first==2){
	    int uu=oy[i+2][id].second,vv=oy[i+2][id-1].second;
	    unionset(uu,vv);
	    ru.push_back(uu); rv.push_back(vv);
	    ra.push_back(xi-1); rb.push_back(i+3);
	  }
	}
	else{
	  ra.push_back(xi+1); rb.push_back(i-1);
	  ba.insert(ii(xi+1,i-1));
	}
      }
    }
  }
  for(int i=2;i<MAX_N;i+=2){
    int t=ox[i].size();
    for(int j=0;j<t-1;j++){
      int yi=ox[i][j].first,yj=ox[i][j+1].first;
      int u=ox[i][j].second,v=ox[i][j+1].second;
      if(yj-yi==2){
	ru.push_back(u); rv.push_back(v);
	unionset(u,v);
	if(ba.find(ii(i-1,yi+1))!=ba.end()){
	  ra.push_back(i+1); rb.push_back(yi+1);
	  ba.insert(ii(i+1,yi+1));
	}
	else{
	  ra.push_back(i-1); rb.push_back(yi+1);
	  ba.insert(ii(i-1,yi+1));
	}
      }
    }
  }
  if(tam[findset(0)]!=n) return 0;
  build(ru,rv,ra,rb);
  return 1;
}

컴파일 시 표준 에러 (stderr) 메시지

parks.cpp: In function 'int construct_roads(std::vector<int>, std::vector<int>)':
parks.cpp:50:6: warning: unused variable 'xk' [-Wunused-variable]
   50 |  int xk=oy[i][j+2].first;
      |      ^~

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 0 / 15
• Subtask 4: 0 / 20
• Subtask 5: 0 / 20
• Subtask 6: 0 / 30