Submission #975306

#	Time	Username	Problem	Language	Result	Execution time	Memory
975306		raspy	Connecting Supertrees (IOI20_supertrees)	C++14	21 / 100	153 ms	22684 KiB

supertrees

#include "supertrees.h"
#include <vector>
#include <iostream>

using namespace std;

bool obd[20005];
int dis[20005];
vector<int> el[20005];

int par(int x)
{
	return dis[x] = (dis[x] == x ? x : par(dis[x]));
}

void zd(int x, int y, bool zlij = true)
{
	x = par(x);
	y = par(y);
	if (x == y)
		return;
	if (el[x].size() < el[y].size())
		swap(x, y);
	if (zlij)
	{
		for (auto e : el[y])
			el[x].push_back(e);
	}
	el[y].clear();
	dis[y] = x;
	return;
}

int construct(vector<vector<int>> p)
{
	int n = p.size();
	vector<vector<int>> gr(n, vector<int>(n, 0));
	for (int i = 0; i < n; i++)
	{
		el[i].push_back(i);
		dis[i] = i;
	}
	for (int i = 0; i < n; i++)
		for (int j = i+1; j < n; j++)
		{
			if (p[i][j] == 1 && par(i)-par(j))
			{
				gr[par(i)][par(j)] = gr[par(j)][par(i)] = 1;
				zd(i, j, 0);
			}
		}
	int dalje = 0;
	for (int i = 0; i < n; i++)
		for (int j = i+1; j < n; j++)
		{
			if (p[i][j] == 2 && par(i)-par(j))
			{
				dalje = 1;
				zd(i, j);
			}
		}
	if (dalje)
	{
		for (int i = 0; i < n; i++)
		{
			int x = par(i);
			if (obd[x])
				continue;
			obd[x] = 1;			
			vector<int> tr = el[x];
			if (tr.size() <= 2)
				return 0;
			tr.push_back(x);
			int pr = x;
			for (auto v : el[x])
				gr[v][pr] = gr[pr][v] = 1;
		}
	}
	for (int i = 0; i < n; i++)
		for (int j = i+1; j < n; j++)
			if (p[i][j] == 0 && par(i) == par(j))
				return 0;
	build(gr);
	return 1;
}

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