Submission #975303

#	Time	Username	Problem	Language	Result	Execution time	Memory
975303		raspy	Connecting Supertrees (IOI20_supertrees)	C++14	11 / 100	155 ms	24660 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);
			}
		}
	for (int i = 0; i < n; i++)
	{
		int x = par(i);
		if (obd[x])
			continue;
		obd[x] = true;
		vector<int> dv;
		for (int j = 0; j < n; j++)
		{
			if (p[x][j] == 2)
			{
				if (par(x) == par(j) || el[j].empty())
					return 0;
				zd(x, j, false);
				dv.push_back(j);
			}
		}
		vector<int>& vsi = el[i];
		for (int k = 1; k < vsi.size(); k++)
		{
			int cnt = 0;
			for (int j = 0; j < n; j++)
			{
				if (p[vsi[k]][j] == 2)
				{
					if (par(vsi[k]) != par(j))
						return 0;
					zd(vsi[k], j, false);
					cnt++;
				}
			}
			if (cnt != dv.size())
				return 0;
		}
		if (!dv.empty())
		{
			if (dv.size() < 2)
				return 0;
			gr[x][dv[0]] = 1;
			gr[dv[0]][x] = 1;
			dv.push_back(x);
			for (int k = 0; k < dv.size()-1; k++)
				gr[dv[k]][dv[k+1]] = gr[dv[k+1]][dv[k]] = 1;
		}
	}
	build(gr);
	return 1;
}

Compilation message (stderr)

supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:70:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   70 |   for (int k = 1; k < vsi.size(); k++)
      |                   ~~^~~~~~~~~~~~
supertrees.cpp:83:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   83 |    if (cnt != dv.size())
      |        ~~~~^~~~~~~~~~~~
supertrees.cpp:93:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   93 |    for (int k = 0; k < dv.size()-1; k++)
      |                    ~~^~~~~~~~~~~~~

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