Submission #306330

#	Time	Username	Problem	Language	Result	Execution time	Memory
306330		andreiomd	Connecting Supertrees (IOI20_supertrees)	C++14	40 / 100	263 ms	31100 KiB

supertrees

#include "supertrees.h"
#include <vector>

using namespace std;

const int NMAX = 1e3 + 1;

int N;
int roads[NMAX][NMAX];

vector < int > tree[NMAX], cycle[NMAX];

bool Edge[NMAX][NMAX];

vector < int > line;
vector < vector < int > > ans;

bool Sel_tree[NMAX], Sel_cycle[NMAX];
int Id_tree[NMAX], Id_cycle[NMAX];

vector < int > List;
bool OK = 1;

static inline void Add_Edge (int X, int Y)
{
    Edge[X][Y] = Edge[Y][X] = 1;

    return;
}

static inline void DFS_tree(int Node, int Id)
{
    Sel_tree[Node] = 1, Id_tree[Node] = Id;

    for(auto it : tree[Node])
        if(!Sel_tree[it])
            Add_Edge(Node, it), DFS_tree(it, Id);

    return;
}

static inline void Build_trees ()
{
    for(int i = 1; i <= N; ++i)
        if(!tree[i].empty() && !Sel_tree[i])
            DFS_tree(i, i);

    return;
}

static inline void DFS_cycle (int Node, int Id)
{
    List.push_back(Node);

    Sel_cycle[Node] = 1, Id_cycle[Node] = Id;

    for(auto it : cycle[Node])
        if(!Sel_cycle[it])
            Add_Edge(Node, it), DFS_cycle(it, Id);

    return;
}

static inline void Build_cycles ()
{
    for(int i = 1; i <= N; ++i)
        if(!cycle[i].empty() && !Sel_cycle[i])
        {
            List.clear(), DFS_cycle(i, i);

            if((int)List.size() > 2)
                Add_Edge(i, List[(int)List.size() - 1]);
            else
                OK = 0;
        }

    return;
}

static inline void Solve ()
{
    Build_trees();

    Build_cycles();

    return;
}

static inline void Reconstruct ()
{
    for(int i = 1; i <= N; ++i)
    {
        line.clear();

        for(int j = 1; j <= N; ++j)
            line.push_back(Edge[i][j]);

        ans.push_back(line);
    }

    return;
}

static inline bool Check ()
{
    for(int i = 1; i < N; ++i)
        for(int j = i + 1; j <= N; ++j)
            if(roads[i][j] == 0)
            {
                if(Id_tree[i] == Id_tree[j] && Id_tree[i])
                    return 0;

                if(Id_cycle[i] == Id_cycle[j] && Id_cycle[i])
                    return 0;
            }

    return (1 & OK);
}

int construct (vector < vector < int > > p)
{
    N = (int)p.size();

    for(int i = 0; i < N; ++i)
        for(int j = 0; j < N; ++j)
        {
            roads[i + 1][j + 1] = p[i][j];

            if(i == j)
                continue;

            if(p[i][j] == 1)
                tree[i + 1].push_back(j + 1);
            else if(p[i][j] == 2)
                cycle[i + 1].push_back(j + 1);
            else if(p[i][j] == 3)
                return 0;
        }

    Solve();

    if(!Check())
        return 0;

    Reconstruct();

    build(ans);

    return 1;
}

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