oj.uz

Submission #557562

# Submission time Handle Problem Language Result Execution time Memory
557562 2022-05-05T13:10:24 Z timreizin Parachute rings (IOI12_rings) C++17
37 / 100
 3129 ms 121660 KB 
#include <vector>
#include <numeric>
#include <array>
#include <algorithm>

using namespace std;

struct DSU
{
    int n, comps;
    vector<int> parent, size;
    vector<int> adj;
    array<int, 5> counter;
    int res, v;

    DSU(int n = 0, int v = -1) : n(n), v(v)
    {
        parent.resize(n);
        size.resize(n, 1);
        iota(parent.begin(), parent.end(), 0);
        comps = n;
        adj.resize(n);
        counter.fill(0);
        counter[0] = n;
        res = (v == -1 ? n : 1);
    }

    int getParent(int i)
    {
        if (parent[i] == i) return i;
        return parent[i] = getParent(parent[i]);
    }

    void unite(int a, int b)
    {
        if (res == 0) return;
        if (a == v || b == v) return;
        int wasCyc = comps - counter[0] - counter[1] / 2;
        --counter[min(adj[a], 4)];
        --counter[min(adj[b], 4)];
        ++adj[a];
        ++adj[b];
        ++counter[min(adj[a], 4)];
        ++counter[min(adj[b], 4)];
        if (counter[3] + counter[4] > 0)
        {
            res = 0;
            return;
        }
        a = getParent(a);
        b = getParent(b);
        if (a != b) --comps;
        int newCyc = comps - counter[0] - counter[1] / 2;
        if (v != -1 && newCyc > 0)
        {
            res = 0;
            return;
        }
        else if (v == -1)
        {
            if (newCyc >= 2)
            {
                res = 0;
                return;
            }
            if (newCyc == 1 && wasCyc == 0)
            {
                vector<int> cnt(n);
                for (int i = 0; i < n; ++i)
                {
                    if (adj[i] < 2) cnt[getParent(i)] = -1e9;
                    else ++cnt[getParent(i)];
                }
                res = 0;
                for (int i = 0; i < n; ++i) res = max(res, cnt[i]);
            }
        }
        if (a != b)
        {
            if (size[a] < size[b]) swap(a, b);
            size[a] += size[b];
            parent[b] = a;
        }
    }

};

int n;
vector<vector<int>> adj;
array<DSU, 8> dsu;
array<int, 5> counter;
vector<int> curs, dop;
vector<pair<int, int>> edges;

void Init(int N_)
{
    n = N_;
    adj.resize(n);
    dsu[0] = DSU(n);
    counter[0] = n;
    curs.push_back(-1);
}

void Link(int a, int b)
{
    int was3 = counter[3], was4 = counter[4];
    --counter[min((int)adj[a].size(), 4)];
    --counter[min((int)adj[b].size(), 4)];
    adj[a].push_back(b);
    adj[b].push_back(a);
    ++counter[min((int)adj[a].size(), 4)];
    ++counter[min((int)adj[b].size(), 4)];
    if (counter[4] > 1) return;
    if (counter[4] > was4)
    {
        curs.clear();
        dop.clear();
        for (int i = 0; i < 7; ++i) dsu[i].res = 0;
        if (adj[a].size() == 4) curs.push_back(a);
        if (adj[b].size() == 4) curs.push_back(b);
        dsu[0] = DSU(n, curs[0]);
        for (auto [a, b] : edges) dsu[0].unite(a, b);
    }
    else if (counter[3] > was3)
    {
        if (counter[3] > 4 && was3 <= 4)
        {
            curs.clear();
            dop.clear();
            for (int i = 0; i < 7; ++i) dsu[i].res = 0;
        }
        if (counter[3] <= 4)
        {
            if (was3 == 0) curs.clear();
            if (adj[a].size() == 3) curs.push_back(a);
            if (adj[b].size() == 3) curs.push_back(b);
            for (int i = 0; i < 7; ++i) dsu[i].res = 0;
            dop.clear();
            for (int i = 0; i < curs.size(); ++i)
            {
                dsu[i] = DSU(n, curs[i]);
                for (auto [a, b]: edges) dsu[i].unite(a, b);
            }
            //calc dop
            if (curs.size() < 3)
            {
                for (int i = 0; i < n; ++i)
                {
                    if (adj[i].size() < 3)
                    {
                        bool was0 = false, was1 = curs.size() == 1;
                        for (int j: adj[i])
                        {
                            was0 = was0 || (j == curs[0]);
                            if (curs.size() == 2) was1 = was0 || (j == curs[1]);
                        }
                        if (was0 && was1)
                        {
                            dop.push_back(i);
                        }
                    }
                }
            }
            for (int i = 0; i < dop.size(); ++i)
            {
                dsu[i + curs.size()] = DSU(n, dop[i]);
                for (auto [a, b]: edges) dsu[i + curs.size()].unite(a, b);
            }
        }
    }
    for (int i = 0; i < curs.size(); ++i) dsu[i].unite(a, b);
    for (int i = 0; i < dop.size(); ++i) dsu[i + curs.size()].unite(a, b);
    edges.emplace_back(a, b);
}

int CountCritical()
{
    if (counter[4] > 1) return 0;
    int res = 0;
    for (int i = 0; i < 8; ++i) res += dsu[i].res;
    return res;
}

Compilation message

rings.cpp: In function 'void Link(int, int)':
rings.cpp:139:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  139 |             for (int i = 0; i < curs.size(); ++i)
      |                             ~~^~~~~~~~~~~~~
rings.cpp:164:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  164 |             for (int i = 0; i < dop.size(); ++i)
      |                             ~~^~~~~~~~~~~~
rings.cpp:171:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  171 |     for (int i = 0; i < curs.size(); ++i) dsu[i].unite(a, b);
      |                     ~~^~~~~~~~~~~~~
rings.cpp:172:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  172 |     for (int i = 0; i < dop.size(); ++i) dsu[i + curs.size()].unite(a, b);
      |                     ~~^~~~~~~~~~~~

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 3 ms 724 KB Output is correct
3 Correct 2 ms 852 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 2 ms 468 KB Output is correct
6 Correct 3 ms 724 KB Output is correct
7 Correct 1 ms 724 KB Output is correct
8 Correct 2 ms 596 KB Output is correct
9 Correct 4 ms 904 KB Output is correct
10 Correct 6 ms 852 KB Output is correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 437 ms 38972 KB Output is correct
2 Correct 1184 ms 87808 KB Output is correct
3 Correct 760 ms 121660 KB Output is correct
4 Correct 1118 ms 78440 KB Output is correct
5 Correct 1119 ms 78536 KB Output is correct
6 Correct 1053 ms 77052 KB Output is correct
7 Correct 688 ms 109432 KB Output is correct
8 Correct 2414 ms 111832 KB Output is correct
9 Correct 3129 ms 121516 KB Output is correct
10 Correct 901 ms 76232 KB Output is correct

Subtask #3
0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 3 ms 724 KB Output is correct
3 Correct 2 ms 852 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 2 ms 468 KB Output is correct
6 Correct 3 ms 724 KB Output is correct
7 Correct 1 ms 724 KB Output is correct
8 Correct 2 ms 596 KB Output is correct
9 Correct 4 ms 904 KB Output is correct
10 Correct 6 ms 852 KB Output is correct
11 Correct 5 ms 944 KB Output is correct
12 Correct 12 ms 1492 KB Output is correct
13 Correct 10 ms 1528 KB Output is correct
14 Incorrect 4 ms 1236 KB Output isn't correct
15 Halted 0 ms 0 KB -

Subtask #4
0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 3 ms 724 KB Output is correct
3 Correct 2 ms 852 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 2 ms 468 KB Output is correct
6 Correct 3 ms 724 KB Output is correct
7 Correct 1 ms 724 KB Output is correct
8 Correct 2 ms 596 KB Output is correct
9 Correct 4 ms 904 KB Output is correct
10 Correct 6 ms 852 KB Output is correct
11 Correct 5 ms 944 KB Output is correct
12 Correct 12 ms 1492 KB Output is correct
13 Correct 10 ms 1528 KB Output is correct
14 Incorrect 4 ms 1236 KB Output isn't correct
15 Halted 0 ms 0 KB -

Subtask #5
0 / 31.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 3 ms 724 KB Output is correct
3 Correct 2 ms 852 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 2 ms 468 KB Output is correct
6 Correct 3 ms 724 KB Output is correct
7 Correct 1 ms 724 KB Output is correct
8 Correct 2 ms 596 KB Output is correct
9 Correct 4 ms 904 KB Output is correct
10 Correct 6 ms 852 KB Output is correct
11 Correct 437 ms 38972 KB Output is correct
12 Correct 1184 ms 87808 KB Output is correct
13 Correct 760 ms 121660 KB Output is correct
14 Correct 1118 ms 78440 KB Output is correct
15 Correct 1119 ms 78536 KB Output is correct
16 Correct 1053 ms 77052 KB Output is correct
17 Correct 688 ms 109432 KB Output is correct
18 Correct 2414 ms 111832 KB Output is correct
19 Correct 3129 ms 121516 KB Output is correct
20 Correct 901 ms 76232 KB Output is correct
21 Correct 5 ms 944 KB Output is correct
22 Correct 12 ms 1492 KB Output is correct
23 Correct 10 ms 1528 KB Output is correct
24 Incorrect 4 ms 1236 KB Output isn't correct
25 Halted 0 ms 0 KB -