Submission #896593

#	Time	Username	Problem	Language	Result	Execution time	Memory
896593		LCJLY	Connecting Supertrees (IOI20_supertrees)	C++14	100 / 100	186 ms	22444 KiB

supertrees

#include "supertrees.h"
#include <bits/stdc++.h>
using namespace std;
#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:x) cout << it << " "; cout << #y << endl;

struct DSU{
	vector<int>e;
	vector<int>storage[1005];
	void init(int n){
		e=vector<int>(n,-1);
		for(int x=0;x<n;x++){
			storage[x].push_back(x);
		}
	}
	
	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);}
	
	int size(int x){return -e[get(x)];}
	
	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];
		for(auto it:storage[y]) storage[x].push_back(it);
		e[y]=x;
		return 1;
	}
};

int construct(vector<vector<int>> p) {
	int n=p.size();
	DSU one;
	one.init(n+5);
	DSU two;
	two.init(n+5);
	DSU three;
	three.init(n+5);
	
	for(int x=0;x<n;x++){
		for(int y=0;y<n;y++){
			if(p[x][y]==1){
				one.unite(x,y);
			}
			else if(p[x][y]==2){
				two.unite(x,y);
			}
			else if(p[x][y]==3){
				return 0;
			}
		}
	}
	
	vector<vector<int>>ans;
	ans.resize(n);
	for(int x=0;x<n;x++){
		for(int y=0;y<n;y++){
			ans[x].push_back(0);
		}
	}
	
	bool done[n+5];
	memset(done,0,sizeof(done));
	for(int x=0;x<n;x++){
		if(one.get(x)==x){
			int last=-1;
			for(auto it:one.storage[x]){
				if(last!=-1){
					ans[last][it]=1;
					ans[it][last]=1;
					done[it]=true;
				}
				last=it;
			}
			
			for(auto it:one.storage[x]){
				for(auto it2:one.storage[x]){
					if(p[it][it2]!=1) return 0;
				}
			}
		}
	}
	
	for(int x=0;x<n;x++){
		if(two.get(x)==x&&two.size(x)>1){
			if(two.size(x)==2) return 0;
			int last=-1;
			for(auto it:two.storage[x]){
				if(done[it]) continue; 
				if(last!=-1){
					ans[last][it]=1;
					ans[it][last]=1;
				}
				last=it;
			}
			if(last!=-1){
				ans[last][two.storage[x][0]]=1;
				ans[two.storage[x][0]][last]=1;
			}
			for(auto it:two.storage[x]){
				for(auto it2:two.storage[x]){
					if(it==it2) continue;
					if(one.sameSet(it,it2)) continue;
					if(p[it][it2]!=2) return 0;
				}
			}
		}
	}

	build(ans);
	return 1;
}

• Subtask 1: 11 / 11
• Subtask 2: 10 / 10
• Subtask 3: 19 / 19
• Subtask 4: 35 / 35
• Subtask 5: 21 / 21
• Subtask 6: 4 / 4