Submission #1108742

#	Time	Username	Problem	Language	Result	Execution time	Memory
1108742		SteveBro	Connecting Supertrees (IOI20_supertrees)	C++17	100 / 100	182 ms	24144 KiB

supertrees

#include <bits/stdc++.h>
#include "supertrees.h"
using namespace std;
vector <vector<int>> sol;
int sef[1001];
int ef(int x)
{
    if(sef[x]==x)
        return x;
    else
        return sef[x]=ef(sef[x]);
}
vector <int> comp[1001],rez,l;
bool ok[1001];
int construct(vector <vector <int>> p)
{
    int i,j,nr,n;
    n=p.size();
    for(i=0;i<n;i++)
        sef[i]=i;
    l.resize(n);
    for(i=0;i<n;i++)
        sol.push_back(l);
    for(i=0;i<n;i++)
    {
        for(j=0,nr=0;j<n;j++)
        {
            if(p[i][j]==3)
                return 0;
            if(p[i][j]==0&&ef(i)==ef(j))
                return 0;
            if(p[i][j]>0)
                sef[ef(i)]=ef(j);
            if(p[i][j]==2)
                nr++;
            if(p[i][j]==1&&i!=j)
                ok[i]=true;
        }
        if(nr==1)
            return 0;
    }
    for(i=0;i<n;i++)
        comp[ef(i)].push_back(i);
    for(i=0;i<n;i++)
        sef[i]=-1;
    for(i=0;i<n;i++)
    {
        if(!comp[i].empty())
        {
            rez.clear();
            for(auto x : comp[i])
            {
                if(!ok[x])/// se alfa pe ciclu
                    rez.push_back(x);
                else
                {
                    if(sef[x]==-1)///nou lant
                    {
                        rez.push_back(x);
                        sef[x]=x;
                        for(j=0;j<n;j++)
                        {
                            if(p[x][j]==1&&x!=j)
                            {
                                if(sef[j]==-1)
                                {
                                    sef[j]=x;
                                    sol[x][j]=sol[j][x]=1;
                                }
                                else
                                    return 0;
                            }
                        }
                    }
                    else
                    {
                        for(j=0;j<n;j++)
                        {
                            if(p[x][j]==2&&sef[x]==sef[j])
                                return 0;
                            if(p[x][j]==1&&sef[x]!=sef[j])
                                return 0;
                        }
                    }
                }
            }
            if(rez.size()>2)
            {
                for(j=1;j<rez.size();j++)
                {
                    sol[rez[j-1]][rez[j]]=sol[rez[j]][rez[j-1]]=1;
                }
                sol[rez[0]][rez[j-1]]=sol[rez[j-1]][rez[0]]=1;
            }
        }
    }
    build(sol);
    return 1;
}

Compilation message (stderr)

supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:89:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   89 |                 for(j=1;j<rez.size();j++)
      |                         ~^~~~~~~~~~~

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