Submission #756332

#	Time	Username	Problem	Language	Result	Execution time	Memory
756332		Trumling	Connecting Supertrees (IOI20_supertrees)	C++14	21 / 100	209 ms	26068 KiB

supertrees

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

typedef long long ll;
#define pb push_back
#define F first
#define S second
#define enter cout<<'\n';
#define INF 99999999999999999
#define MOD 1000000007
#define all(x) x.begin(),x.end()

vector<bool>vis(1000,0);
vector<bool>vis2(1000,0);

vector<vector<int>>g;
vector<vector<int>>ans;
ll nn;

bool dfs1(int start,int beg)
{
	vis[start]=1;
	for(int i=0;i<nn;i++)
		if(g[start][i]!=g[beg][i] && i!=start && i!=beg)
			return 0;

	for(int i=0;i<nn;i++)
		if(!vis[i] && g[start][i]==1)
		{
			ans[i][start]=1;
			ans[start][i]=1;
			return dfs1(i,beg);
		}

	vis[beg]=0;

	return 1;
}

bool dfs2(int start,int beg)
{
	vis[start]=1;
	if(start!=beg)
	for(int i=0;i<nn;i++)
	{
		if(g[start][i]==1 && g[beg][i]==1)
		return 0;

		if(g[start][i]==2 && g[beg][i]==0 || g[start][i]==0 && g[beg][i]==2)
		return 0;

		if(g[start][i]==1 && g[beg][i]==0 || g[start][i]==0 && g[beg][i]==1)
		return 0;
	}

	ll count=0;
	for(int i=0;i<nn;i++)
		if(g[start][i]==2 && !vis[i])
		count++;

	if(count==1)
	{
		assert(0);
		assert(1);
		return 0;
	}
	

	for(int i=0;i<nn;i++)
		if(!vis[i] && g[start][i]==2)
		{
			ans[i][start]=1;
			ans[start][i]=1;

			return dfs2(i,beg);
		}
	ans[start][beg]=1;
	ans[beg][start]=1;
	return 1;
}

int construct(vector<vector<int>> pr) 
{
	nn=pr.size();
	g=pr;

	ans.assign(nn,vector<int>(nn,0));

	for(int i=0;i<nn;i++)
	{
		bool now=dfs1(i,i);
		if(!now)
		return 0;
	}

	for(int i=0;i<nn;i++)
	{
		if(vis[i])
		continue;

		bool now=dfs2(i,i);
		if(!now)
		return 0;
	}

	for(int i=0;i<nn;i++)
	ans[i][i]=0;

	build(ans);
	return 1;

}

Compilation message (stderr)

supertrees.cpp: In function 'bool dfs2(int, int)':
supertrees.cpp:50:21: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   50 |   if(g[start][i]==2 && g[beg][i]==0 || g[start][i]==0 && g[beg][i]==2)
supertrees.cpp:53:21: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   53 |   if(g[start][i]==1 && g[beg][i]==0 || g[start][i]==0 && g[beg][i]==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