Submission #776814

#	Time	Username	Problem	Language	Result	Execution time	Memory
776814		Minindu206	Connecting Supertrees (IOI20_supertrees)	C++14	0 / 100	1 ms	304 KiB

supertrees

#include "supertrees.h"
#include <vector>
#include<bits/stdc++.h>
using namespace std;
struct DSU
{
	/* data */
	int n;
	vector<int> par, sz;
	void init(int _n)
	{
		n = _n;
		par.resize(n + 1, -1);
		sz.resize(n + 1, 0);
	}
	int finds(int a)
	{
		if(par[a] == -1)
			return a;
		return par[a] = finds(par[a]);
	}
	void unites(int a, int b)
	{
		int x = par[a];
		int y = par[b];
		if(x != y)
		{
			if(sz[x] < sz[y])
				swap(x, y);
			par[y] = x;
			sz[x] += sz[y];
		}
	}
};


int construct(std::vector<std::vector<int>> p) {
	int n = p.size();
	DSU d;
	d.init(n);
	for(int i=0;i<n-1;i++)
	{
		for(int j=i+1;j<n;j++)
		{
			if(p[i][j])
				d.unites(i, j);
		}
	}
	vector<vector<int>> ans(n, vector<int>(n, 0));
	map<int, vector<int>> mp;
	for(int i=0;i<n;i++)
	{
		mp[d.finds(i)].push_back(i);
		for(int j=0;j<n;j++)
		{
			if(i == j)
				continue;
			if(p[i][j] == 0)
				if(d.finds(i) == d.finds(j))
					return 0;
		}		
	}
	for(auto a:mp)
	{
		for(int i=0;i<a.second.size() - 1;i++)
			ans[a.second[i]][a.second[i + 1]] = ans[a.second[i + 1]][a.second[i]] = 1;
	}
	build(ans);
	return 1;
}

Compilation message (stderr)

supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:65:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   65 |   for(int i=0;i<a.second.size() - 1;i++)
      |               ~^~~~~~~~~~~~~~~~~~~~

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