Submission #427876

#	Time	Username	Problem	Language	Result	Execution time	Memory
427876		errorgorn	Port Facility (JOI17_port_facility)	C++17	0 / 100	677 ms	1048580 KiB

port_facility

#include <bits/stdc++.h>
using namespace std;
 
#define ll long long
#define ii pair<int,int>
#define fi first
#define se second
#define endl '\n'
 
#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()
 
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
 
inline void read(int &x){
	x=0;
	
	char ch=getchar_unlocked();
	while (ch&16){
		x=x*10+(ch&15);
		ch=getchar_unlocked();
	}
}
 
const int MOD=1000000007;
 
int n;
ii arr[1000005];
vector<int> al[1000005];
bool col[1000005];
bool vis[1000005];
 
struct node{
	vector<int> v[4000010];
	const int BUF=2000005;
	
	node (){
	}
	
	void update(int i,int j,int k){
		i+=BUF,j+=BUF+1;
		
		for (;i<j;i>>=1,j>>=1){
			if (i&1){
				v[i].pub(k);
				i++;
			}
			if (j&1){
				j--;
				v[j].pub(k);
			}
		}
	}
	
	void query(int i,int k,int idx){
		i+=BUF;
		
		while (i){
			for (auto &it:v[i]) if (arr[it].se<k){
				al[it].pub(idx);
				al[idx].pub(it);
			}
			i>>=1;
		}
	}
} root=node();
 
struct node2{
	int arr[4000010];
	const int BUF=2000005;
	
	node2(){
		memset(arr,-1,sizeof(arr));
	}
	
	void update(int i,int k){
		i+=BUF;
		
		while (i){
			arr[i]=max(arr[i],k);
			i>>=1;
		}
	}
	
	int query(int i,int j){
		i+=BUF,j+=BUF+1;
		int res=-1;
		
		for (;i<j;i>>=1,j>>=1){
			if (i&1){
				res=max(res,arr[i]);
				i++;
			}
			if (j&1){
				j--;
				res=max(res,arr[j]);
			}
		}
		
		return res;
	}
} white=node2(),black=node2();

void dfs(int i,int p){
	vis[i]=true;
	
	for (auto &it:al[i]){
		if (it==p) continue;
		col[it]=!col[i];
		dfs(it,i);
	}
}

int ans=1;
 
int main(){
	cin.tie(0);
	cout.tie(0);
	cin.sync_with_stdio(false);
	
	read(n);
	
	rep(x,0,n){
		read(arr[x].fi),read(arr[x].se);
	}
	
	sort(arr,arr+n,[](ii i,ii j){
		return i.se<j.se;
	});
	
	rep(x,0,n){
		//cout<<"arr: "<<x<<" "<<arr[x].fi<<" "<<arr[x].se<<endl;
		root.query(arr[x].fi,arr[x].se,x);
		root.update(arr[x].fi,arr[x].se,x);
	}
	
	rep(x,0,n) if (!vis[x]){
		dfs(x,-1);
		ans=2*ans%MOD;
	}
	
	rep(x,0,n){
		if (!col[x]){ //white
			white.update(arr[x].fi,arr[x].se);
		}
		else{ //black
			black.update(arr[x].fi,arr[x].se);
		}
	}
	
	rep(x,0,n){
		if (!col[x]){ //white
			if (white.query(arr[x].fi,arr[x].se)>arr[x].se) ans=0;
		}
		else{ //black
			if (black.query(arr[x].fi,arr[x].se)>arr[x].se) ans=0;
		}
	}
	
	cout<<ans<<endl;
}

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