Submission #435487

#	Time	Username	Problem	Language	Result	Execution time	Memory
435487		errorgorn	Fountain Parks (IOI21_parks)	C++17	100 / 100	805 ms	32088 KiB

parks

#include "parks.h"
 
#include <bits/stdc++.h>
using namespace std;
 
#define ll long long
#define ii pair<ll,ll>
#define fi first
#define se second
 
#define puf push_front
#define pof pop_front
#define pub push_back
#define pob pop_back
#define lb lower_bound
#define ub upper_bound
 
#define rep(x,s,e) for (auto x=s-(s>e);x!=e-(s>e);s<e?x++:x--)
#define all(x) (x).begin(),(x).end()
#define sz(x) (int) (x).size()
 
struct UFDS{
	int p[200005];
 
	UFDS(){
		rep(x,0,200005) p[x]=x;
	}
 
	int parent(int i){
		if (p[i]==i) return i;
		else return p[i]=parent(p[i]);
	}
 
	void unions(int i,int j){
		i=parent(i),j=parent(j);
		p[i]=j;
	}
} ufds;
 
int n;
ii arr[200005];
 
//return values
vector<int> id1,id2;
vector<int> bx,by;
 
map<ii,int> id;
 
int construct_roads(std::vector<int> X, std::vector<int> Y) {
    n=sz(X);
 
    rep(x,0,n) arr[x]=ii(X[x],Y[x]);
 
    rep(x,0,n) id[arr[x]]=x;
 
    rep(x,0,n){
		int i,j;
		tie(i,j)=arr[x];
 
		if (id.count(ii(i,j+2))){ //vertical
			int temp=id[ii(i,j+2)];
			ufds.unions(x,temp);
 
			//cout<<"ver: "<<x<<" "<<temp<<endl;
 
			if ((i+j)%4==0){ //left
				id1.pub(x);
				id2.pub(temp);
 
				bx.pub(i-1);
				by.pub(j+1);
			}
			else{
				//right if possible
 
				if (!id.count(ii(i+2,j)) || !id.count(ii(i+2,j+2))){
					id1.pub(x);
					id2.pub(temp);
 
					bx.pub(i+1);
					by.pub(j+1);
				}
			}
		}
		if (id.count(ii(i+2,j))){ //horizontal
			int temp=id[ii(i+2,j)];
			ufds.unions(x,temp);
 
			//cout<<"hor: "<<x<<" "<<temp<<endl;
 
			if (j%4==0){
				if (i%4==0){ //up
					id1.pub(x);
					id2.pub(temp);
 
					bx.pub(i+1);
					by.pub(j+1);
				}
				else{ //down
					id1.pub(x);
					id2.pub(temp);
 
					bx.pub(i+1);
					by.pub(j-1);
				}
			}
			else{
				if (i%4==0){ //down if possible
					if (!id.count(ii(i,j-2)) || !id.count(ii(i+2,j-2))){
						id1.pub(x);
						id2.pub(temp);
 
						bx.pub(i+1);
						by.pub(j-1);
					}
				}
				else{ //up if possible
					if (!id.count(ii(i,j+2)) || !id.count(ii(i+2,j+2))){
						id1.pub(x);
						id2.pub(temp);
 
						bx.pub(i+1);
						by.pub(j+1);
					}
				}
			}
		}
	}
 
	rep(x,0,n) if (ufds.parent(0)!=ufds.parent(x)) return 0;
 
	build(id1,id2,bx,by);
 
	return 1;
}

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