제출 #975388

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
975388		LCJLY	Port Facility (JOI17_port_facility)	C++14	22 / 100	6067 ms	422340 KiB

port_facility

#include <bits/stdc++.h>
using namespace std;
 
#define int long long 
#define ld long double
#define show(x,y) cout << y << " " << #x << endl;
#define show2(x,y,i,j) cout << y << " " << #x << "  " << j << " " << #i << endl;
#define show3(x,y,i,j,p,q) cout << y << " " << #x << "  " << j << " " << #i << "  " << q << " " << #p << endl;
#define show4(x,y) for(auto it:y) cout << it << " "; cout << #x << endl;
typedef pair<long long,long long>pii;
typedef array<int,5>pi2;
mt19937_64 rng(chrono::system_clock::now().time_since_epoch().count());

inline pii combine(pii a, pii b){
	if(a.first>b.first){
		return a;
	}
	else return b;
}

struct node{
	int s,e,m;
	node *l,*r;
	pii v;
	
	node(int ss, int ee):s(ss),e(ee),m((s+e)>>1){
		if(s!=e){
			l=new node(s,m);
			r=new node(m+1,e);
			v=combine(l->v,r->v);
		}
		else{
			v={0,s};
		}
	}
	
	void upd(int x, pii y){
		if(s==e){
			v=y;
			return;
		}
		if(x<=m) l->upd(x,y);
		else r->upd(x,y);
		v=combine(l->v,r->v);
	}
	
	pii query(int x, int y){
		if(x<=s&&y>=e){
			return v;
		}
		if(y<=m) return l->query(x,y);
		if(x>m) return r->query(x,y);
		return combine(l->query(x,m),r->query(m+1,y)); 
	}
};

vector<int>adj[1000005];
int visited[1000005];
bool amos=true;
const int mod=1e9+7;

void dfs(int index, int col){
	visited[index]=col;
	for(auto it:adj[index]){
		if(visited[it]&&visited[it]==visited[index]) amos=false;
		else if(!visited[it]){
			dfs(it,3-col);
		}
	}
}

struct DSU{
	vector<int>e;
	void init(int n){
		e=vector<int>(n,-1);
	}
	
	int get(int x){
		return e[x]<0?x:e[x]=get(e[x]);
	}
	
	bool sameSet(int x, int y){
		return get(x)==get(y);
	}
	
	bool unite(int x, int y){
		x=get(x);
		y=get(y);
		if(x==y) return 0;
		if(e[x]>e[y]) swap(x,y);
		e[x]+=e[y];
		e[y]=x;
		return 1;
	}
};

void solve(){
	int n;
	cin >> n;
	pii arr[n];
	for(int x=0;x<n;x++){
		cin >> arr[x].first >> arr[x].second;
	}
	
	sort(arr,arr+n);
	
	DSU dsu;
	dsu.init(2*n+5);
	node st(0,2*n+5);
	for(int x=0;x<n;x++){
		st.upd(arr[x].first,{arr[x].second,x});
	}
	
	for(int x=0;x<n;x++){
		vector<pii>undo;
		st.upd(arr[x].first,{0,x});
		while(1){
			pii hold=st.query(arr[x].first,arr[x].second);
			if(hold.first<=arr[x].second) break;
			adj[x].push_back(hold.second);
			adj[hold.second].push_back(x);
			dsu.unite(x,hold.second+n);
			dsu.unite(x+n,hold.second);
			if(dsu.sameSet(x,x+n)||dsu.sameSet(hold.second,hold.second+n)){
				cout << 0;
				return;
			}
			st.upd(arr[hold.second].first,{0,hold.second});
			undo.push_back(hold);
		}
		for(auto it:undo){
			st.upd(arr[it.second].first,{arr[it.second].second,it.second});
		}	
	}
	
	int counter=1;
	for(int x=0;x<n;x++){
		if(!visited[x]){
			dfs(x,1);
			counter=(counter*2)%mod;
		}
	}
	
	if(!amos){
		cout << 0;
	}
	else cout << counter;
}
 
int32_t main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	int t=1;
	//freopen("in.txt","r",stdin);
	//cin >> t;
	while(t--){
		solve();
	}
}

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 0 / 56
• Subtask 4: 0 / 22