Submission #557497

# Submission time Handle Problem Language Result Execution time Memory
557497 2022-05-05T11:51:39 Z timreizin Parachute rings (IOI12_rings) C++17
0 / 100
973 ms 173812 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;
        --counter[adj[a]];
        --counter[adj[b]];
        ++adj[a];
        ++adj[b];
        ++counter[adj[a]];
        ++counter[adj[b]];
        a = getParent(a);
        b = getParent(b);
        if (a == b)
        {
            res = 0;
            return;
        }
        if (counter[3] + counter[4] > 0)
        {
            res = 0;
            return;
        }
        --comps;
        if (size[a] < size[b]) swap(a, b);
        size[a] += size[b];
        parent[b] = a;
    }

};

int n;
vector<vector<int>> adj;
array<DSU, 4> 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[adj[a].size()];
    --counter[adj[b].size()];
    adj[a].push_back(b);
    adj[b].push_back(a);
    ++counter[adj[a].size()];
    ++counter[adj[b].size()];
    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:115:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  115 |             for (int i = 0; i < curs.size(); ++i)
      |                             ~~^~~~~~~~~~~~~
rings.cpp:140:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  140 |             for (int i = 0; i < dop.size(); ++i)
      |                             ~~^~~~~~~~~~~~
rings.cpp:147:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  147 |     for (int i = 0; i < curs.size(); ++i) dsu[i].unite(a, b);
      |                     ~~^~~~~~~~~~~~~
rings.cpp:148:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  148 |     for (int i = 0; i < dop.size(); ++i) dsu[i + curs.size()].unite(a, b);
      |                     ~~^~~~~~~~~~~~
rings.cpp: In function 'int CountCritical()':
rings.cpp:156:47: warning: iteration 4 invokes undefined behavior [-Waggressive-loop-optimizations]
  156 |     for (int i = 0; i < 7; ++i) res += dsu[i].res;
rings.cpp:156:23: note: within this loop
  156 |     for (int i = 0; i < 7; ++i) res += dsu[i].res;
      |                     ~~^~~
rings.cpp: In function 'void Link(int, int)':
rings.cpp:106:52: warning: iteration 4 invokes undefined behavior [-Waggressive-loop-optimizations]
  106 |             for (int i = 0; i < 7; ++i) dsu[i].res = 0;
rings.cpp:106:31: note: within this loop
  106 |             for (int i = 0; i < 7; ++i) dsu[i].res = 0;
      |                             ~~^~~
rings.cpp:113:52: warning: iteration 4 invokes undefined behavior [-Waggressive-loop-optimizations]
  113 |             for (int i = 0; i < 7; ++i) dsu[i].res = 0;
rings.cpp:113:31: note: within this loop
  113 |             for (int i = 0; i < 7; ++i) dsu[i].res = 0;
      |                             ~~^~~
rings.cpp:94:48: warning: iteration 4 invokes undefined behavior [-Waggressive-loop-optimizations]
   94 |         for (int i = 0; i < 7; ++i) dsu[i].res = 0;
rings.cpp:94:27: note: within this loop
   94 |         for (int i = 0; i < 7; ++i) dsu[i].res = 0;
      |                         ~~^~~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 3 ms 724 KB Output is correct
3 Runtime error 2 ms 1492 KB Execution killed with signal 11
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 383 ms 39048 KB Output is correct
2 Runtime error 973 ms 173812 KB Execution killed with signal 11
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 3 ms 724 KB Output is correct
3 Runtime error 2 ms 1492 KB Execution killed with signal 11
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 3 ms 724 KB Output is correct
3 Runtime error 2 ms 1492 KB Execution killed with signal 11
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 3 ms 724 KB Output is correct
3 Runtime error 2 ms 1492 KB Execution killed with signal 11
4 Halted 0 ms 0 KB -