Submission #755095

#	Time	Username	Problem	Language	Result	Execution time	Memory
755095		sofija6	Connecting Supertrees (IOI20_supertrees)	C++14	100 / 100	242 ms	25088 KiB

supertrees

#include "supertrees.h"
#include <bits/stdc++.h>
#define MAXN 1010
using namespace std;
int d[MAXN];
int Root(int p)
{
    while (d[p]!=p)
    {
        d[p]=d[d[p]];
        p=d[p];
    }
    return p;
}
void Join(int p,int q)
{
    d[Root(p)]=d[Root(q)];
}
int construct(std::vector<std::vector<int>> p) {
    int n=p.size();
    for (int i=0;i<n;i++)
    {
        d[i]=i;
        for (int j=0;j<n;j++)
        {
            if (p[i][j]==3 || p[i][j]!=p[j][i])
                return 0;
            if (i==j && p[i][j]!=1)
                return 0;
        }
    }
    vector<int> v[n+2];
    for (int i=0;i<n;i++)
    {
        for (int j=0;j<n;j++)
        {
            if (p[i][j]==1)
                Join(i,j);
        }
    }
    vector<vector<int> > b;
    b.resize(n);
    for (int i=0;i<n;i++)
        b[i].resize(n);
    for (int i=0;i<n;i++)
    {
        if (i==Root(i))
            continue;
        b[i][Root(i)]=1;
        b[Root(i)][i]=1;
    }
    bool cyc[n+2][n+2];
    for (int i=0;i<n;i++)
    {
        for (int j=0;j<n;j++)
            cyc[i][j]=false;
    }
    for (int i=0;i<n;i++)
    {
        for (int j=0;j<n;j++)
        {
            if (p[i][j]==2)
                cyc[Root(i)][Root(j)]=true;
        }
    }
    vector<int> root[n+2];
    for (int i=0;i<n;i++)
    {
        root[Root(i)].push_back(i);
        for (int j=0;j<n;j++)
        {
            if (!p[i][j] && (Root(i)==Root(j) || cyc[Root(i)][Root(j)]))
                return 0;
            if (p[i][j]==1 && (Root(i)!=Root(j) || cyc[Root(i)][Root(j)]))
                return 0;
            if (p[i][j]==2 && (Root(i)==Root(j) || !cyc[Root(i)][Root(j)]))
                return 0;
        }
    }
    bool vis[n+2]={false};
    for (int i=0;i<n;i++)
    {
        if (vis[i] || Root(i)!=i)
            continue;
        set<int> s;
        vector<int> v;
        int cur=i;
        while (true)
        {
            s.insert(cur);
            v.push_back(cur);
            vis[cur]=true;
            bool next=false;
            for (int j=0;j<n;j++)
            {
                if (cyc[cur][j] && !s.count(j))
                {
                    cur=j;
                    next=true;
                    break;
                }
            }
            if (!next)
                break;
        }
        if (s.size()==2)
            return 0;
        if (s.size()==1)
            continue;
        for (int j=0;j<v.size();j++)
        {
            for (int k=0;k<v.size();k++)
            {
                if (j==k)
                    continue;
                for (auto U : root[v[j]])
                {
                    for (auto V : root[v[k]])
                    {
                        if (p[U][V]!=2)
                            return 0;
                    }
                }
            }
        }
        for (int j=0;j<v.size()-1;j++)
        {
            b[v[j]][v[j+1]]=1;
            b[v[j+1]][v[j]]=1;
        }
        b[v[v.size()-1]][v[0]]=1;
        b[v[0]][v[v.size()-1]]=1;
    }
    build(b);
    return 1;
}

Compilation message (stderr)

supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:110:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  110 |         for (int j=0;j<v.size();j++)
      |                      ~^~~~~~~~~
supertrees.cpp:112:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  112 |             for (int k=0;k<v.size();k++)
      |                          ~^~~~~~~~~
supertrees.cpp:126:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  126 |         for (int j=0;j<v.size()-1;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