oj.uz

Submission #557554

# Submission time Handle Problem Language Result Execution time Memory
557554 2022-05-05T13:04:15 Z timreizin Parachute rings (IOI12_rings) C++17
37 / 100
 2807 ms 134888 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 < 7; ++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 808 KB Output is correct
8 Correct 2 ms 584 KB Output is correct
9 Correct 4 ms 980 KB Output is correct
10 Correct 4 ms 980 KB Output is correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 457 ms 39004 KB Output is correct
2 Correct 1080 ms 88068 KB Output is correct
3 Correct 707 ms 121720 KB Output is correct
4 Correct 1050 ms 78384 KB Output is correct
5 Correct 1075 ms 92028 KB Output is correct
6 Correct 1046 ms 90036 KB Output is correct
7 Correct 668 ms 121588 KB Output is correct
8 Correct 2199 ms 124492 KB Output is correct
9 Correct 2807 ms 134888 KB Output is correct
10 Correct 814 ms 89148 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 808 KB Output is correct
8 Correct 2 ms 584 KB Output is correct
9 Correct 4 ms 980 KB Output is correct
10 Correct 4 ms 980 KB Output is correct
11 Correct 4 ms 976 KB Output is correct
12 Correct 9 ms 1620 KB Output is correct
13 Correct 11 ms 1748 KB Output is correct
14 Incorrect 3 ms 1364 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 808 KB Output is correct
8 Correct 2 ms 584 KB Output is correct
9 Correct 4 ms 980 KB Output is correct
10 Correct 4 ms 980 KB Output is correct
11 Correct 4 ms 976 KB Output is correct
12 Correct 9 ms 1620 KB Output is correct
13 Correct 11 ms 1748 KB Output is correct
14 Incorrect 3 ms 1364 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 808 KB Output is correct
8 Correct 2 ms 584 KB Output is correct
9 Correct 4 ms 980 KB Output is correct
10 Correct 4 ms 980 KB Output is correct
11 Correct 457 ms 39004 KB Output is correct
12 Correct 1080 ms 88068 KB Output is correct
13 Correct 707 ms 121720 KB Output is correct
14 Correct 1050 ms 78384 KB Output is correct
15 Correct 1075 ms 92028 KB Output is correct
16 Correct 1046 ms 90036 KB Output is correct
17 Correct 668 ms 121588 KB Output is correct
18 Correct 2199 ms 124492 KB Output is correct
19 Correct 2807 ms 134888 KB Output is correct
20 Correct 814 ms 89148 KB Output is correct
21 Correct 4 ms 976 KB Output is correct
22 Correct 9 ms 1620 KB Output is correct
23 Correct 11 ms 1748 KB Output is correct
24 Incorrect 3 ms 1364 KB Output isn't correct
25 Halted 0 ms 0 KB -