Submission #794598

#	Time	Username	Problem	Language	Result	Execution time	Memory
794598		MODDI	Connecting Supertrees (IOI20_supertrees)	C++14	100 / 100	168 ms	24124 KiB

supertrees

//#include "grader.cpp"
#include "supertrees.h"
#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define mp make_pair
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<ll> vl;
struct DSU{
	vi parent, size;
	void init(int n){
		parent.resize(n);
		size.resize(n, 1);
		iota(parent.begin(), parent.end(), 0);
	}
	int get_size(int v){
		return size[v];
	}
	int find_parent(int v){
		if(parent[v] == v)	return v;
		return parent[v] = find_parent(parent[v]);
	}
	void merge(int a, int b){
		a = find_parent(a);
		b = find_parent(b);
		if(a != b){
			if(size[b] > size[a])	swap(a,b);
			
			parent[b] = a;
			size[a] += size[b];
		} 
	}
};
vi G[1001], G2[1001];
int construct(vector<vi> p){
	int n = p.size();
	vector<vi> answer(n, vi(n, 0));
	DSU dsu, dsu2;
	dsu.init(n);
	dsu2.init(n);
	for(int i = 0; i < n; i++){
		for(int j = i + 1; j < n; j++){
			if(p[i][j] == 1)	dsu.merge(i, j);
			if(p[i][j] == 3)	return 0;
		}
	}
	for(int i = 0; i < n; i++){
		G[dsu.find_parent(i)].pb(i);
	}
	for(int i = 0; i < n; i++){
		if(G[i].size() ==0)	continue;
		for(int j = 0; j < (int)G[i].size(); j++){
			for(int k = j+1; k < (int)G[i].size(); k++){
				if(p[G[i][k]][G[i][j]] != 1)	return 0;
			}
		}
		for(int j = 0; j < (int)G[i].size()-1; j++){
			answer[G[i][j]][G[i][j+1]] = 1;
			answer[G[i][j+1]][G[i][j]] = 1;
		}
	}
	for(int i = 0; i < n; i++){
		for(int j = i + 1; j < n; j++){
			if(p[i][j] == 2)
				dsu2.merge(dsu.find_parent(i), dsu.find_parent(j));
		}
	}
	for(int i = 0; i < n; i++){
		if(G[i].size()==0)	continue;
		G2[dsu2.find_parent(i)].pb(i);
	}
	for(int i = 0; i < n; i++){
		if(G2[i].size() < 2)	continue;
		if(G2[i].size() == 2)	return 0;
		for(int j = 0; j < (int)G2[i].size(); j++){
			for(int k = j + 1; k < (int)G2[i].size(); k++){
				for(auto t : G[G2[i][j]]){
					for(auto s : G[G2[i][k]]){
						if(p[t][s] != 2)	return 0;
					}
				}
			}
		}
		for(int j = 0; j < (int)G2[i].size()-1; j++){
			answer[G2[i][j]][G2[i][j+1]] = 1;
			answer[G2[i][j+1]][G2[i][j]] = 1;
		}
		answer[G2[i].back()][G2[i][0]] = 1;
		answer[G2[i][0]][G2[i].back()] = 1;
	}
	build(answer);
	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