Submission #403997

#	Time	Username	Problem	Language	Result	Execution time	Memory
403997		monus1042	Connecting Supertrees (IOI20_supertrees)	C++17	40 / 100	313 ms	27988 KiB

supertrees

#include "supertrees.h"
#include <bits/stdc++.h>
using namespace std;

const int NAX = 1002;
vector<int> parent(NAX, -1);
vector<vector<int> > P(NAX, vector<int>(NAX));
vector<vector<int> > answer;
vector<set<int> > adj(NAX);
int n;

int Find(int u){
	if (parent[u] == -1) return u;
	return parent[u] = Find(parent[u]);
}

int sub12(){
	for (int i=0; i<n; i++){
		for (int j=0; j<n; j++){
			if (i==j) continue;
			int x = Find(i), y = Find(j);
			if (P[i][j] == 1){
				if (x!=y) return 0;
			}else{
				if (x==y) return 0;
			}
		}
	}
	build(answer);
	return 1;
}

int sub3(){
	for (int i=0; i<n; i++){
		for (int j=0; j<n; j++){
			//if (i==j) continue;
			int x = Find(i), y = Find(j);
			if (x == y){
				adj[x].insert(i);
				adj[x].insert(j);
			}
		}
	}
	for (int i=0; i<n; i++){
		if (adj[i].size() > 2){
			for (auto j=adj[i].begin(); j!=adj[i].end(); j++){
				auto nextnode = j;
				nextnode++;
				if (nextnode == adj[i].end()) nextnode = adj[i].begin();
				answer[*j][*nextnode] = answer[*nextnode][*j] = 1;
			}
		}else if (adj[i].size() == 2){
			return 0;
		}
	}
	for (int i=0; i<n; i++){
		for (int j=0; j<n; j++){
			if (i==j) continue;
			int x = Find(i), y = Find(j);
			if (P[i][j] == 0){
				if (x==y) return 0;
			}else{
				if (x!=y) return 0;
			}
		}
	}
	build(answer);
	return 1;
}

int construct(vector<vector<int> > p) {
	n = p.size();
	for (int i=0; i<n; i++){
		vector<int> row(n);
		answer.push_back(row);
	}
	
	int twos = 0;
	for (int i=0; i<n; i++){
		for (int j=0; j<n; j++){
			if (p[i][j] == 2) twos++;
			P[i][j] = p[i][j];
		}
	}
	for (int i=0; i<n; i++){
		for (int j=0; j<n; j++){
			if (i==j) continue;
			if (P[i][j] > 0){
				int x = Find(i), y = Find(j);
				if (x!=y){
					parent[x]=y;
					if (twos == 0) answer[i][j]=answer[j][i]=1;
				}
			}
		}
	}
	if (twos) return sub3();
	else return sub12();
}

• Subtask 1: 11 / 11
• Subtask 2: 10 / 10
• Subtask 3: 19 / 19
• Subtask 4: 0 / 35
• Subtask 5: 0 / 21
• Subtask 6: 0 / 4