oj.uz

Submission #557564

# Submission time Handle Problem Language Result Execution time Memory
557564 2022-05-05T13:11:47 Z timreizin Parachute rings (IOI12_rings) C++17
37 / 100
 2321 ms 121380 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);
            }
            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 = was1 || (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:163:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  163 |             for (int i = 0; i < dop.size(); ++i)
      |                             ~~^~~~~~~~~~~~
rings.cpp:170:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  170 |     for (int i = 0; i < curs.size(); ++i) dsu[i].unite(a, b);
      |                     ~~^~~~~~~~~~~~~
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 < 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 3 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 852 KB Output is correct
10 Correct 4 ms 852 KB Output is correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 428 ms 38876 KB Output is correct
2 Correct 1190 ms 87852 KB Output is correct
3 Correct 715 ms 98264 KB Output is correct
4 Correct 1078 ms 78536 KB Output is correct
5 Correct 1101 ms 78564 KB Output is correct
6 Correct 1036 ms 76968 KB Output is correct
7 Correct 660 ms 97656 KB Output is correct
8 Correct 1876 ms 112072 KB Output is correct
9 Correct 2321 ms 121380 KB Output is correct
10 Correct 766 ms 76368 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 3 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 852 KB Output is correct
10 Correct 4 ms 852 KB Output is correct
11 Correct 4 ms 852 KB Output is correct
12 Correct 9 ms 1492 KB Output is correct
13 Correct 9 ms 1544 KB Output is correct
14 Incorrect 3 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 3 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 852 KB Output is correct
10 Correct 4 ms 852 KB Output is correct
11 Correct 4 ms 852 KB Output is correct
12 Correct 9 ms 1492 KB Output is correct
13 Correct 9 ms 1544 KB Output is correct
14 Incorrect 3 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 3 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 852 KB Output is correct
10 Correct 4 ms 852 KB Output is correct
11 Correct 428 ms 38876 KB Output is correct
12 Correct 1190 ms 87852 KB Output is correct
13 Correct 715 ms 98264 KB Output is correct
14 Correct 1078 ms 78536 KB Output is correct
15 Correct 1101 ms 78564 KB Output is correct
16 Correct 1036 ms 76968 KB Output is correct
17 Correct 660 ms 97656 KB Output is correct
18 Correct 1876 ms 112072 KB Output is correct
19 Correct 2321 ms 121380 KB Output is correct
20 Correct 766 ms 76368 KB Output is correct
21 Correct 4 ms 852 KB Output is correct
22 Correct 9 ms 1492 KB Output is correct
23 Correct 9 ms 1544 KB Output is correct
24 Incorrect 3 ms 1236 KB Output isn't correct
25 Halted 0 ms 0 KB -