oj.uz

Submission #832064

# Submission time Handle Problem Language Result Execution time Memory
832064 2023-08-20T21:53:14 Z finn__ Simurgh (IOI17_simurgh) C++17
51 / 100
 92 ms 3384 KB 
#include "simurgh.h"
#include <bits/stdc++.h>
using namespace std;

namespace quadratic
{
    constexpr size_t N = 240;

    vector<pair<int, int>> g[N];
    int adj[N][N];
    bitset<N *(N - 1) / 2> checked, is_in;

    vector<int> solve(int n, vector<int> u, vector<int> v)
    {
        memset(adj, 255, sizeof adj);
        for (int i = 0; i < u.size(); ++i)
            g[u[i]].emplace_back(v[i], i), g[v[i]].emplace_back(u[i], i), adj[u[i]][v[i]] = adj[v[i]][u[i]] = i;
        vector<int> ans;

        for (int i = 0; i < n; ++i)
        {
            vector<vector<int>> bccs, bcc_trees;
            vector<int> edge_to_bcc;
            bitset<N> visited;
            visited[i] = 1;

            for (auto const &[z, j] : g[i])
                if (!visited[z])
                {
                    queue<int> q({z});
                    visited[z] = 1;
                    edge_to_bcc.push_back(j);
                    vector<int> nodes, edges;

                    while (!q.empty())
                    {
                        int x = q.front();
                        nodes.push_back(x);
                        q.pop();
                        for (auto const &[y, i] : g[x])
                            if (!visited[y])
                            {
                                edges.push_back(i);
                                q.push(y);
                                visited[y] = 1;
                            }
                    }

                    bccs.push_back(nodes);
                    bcc_trees.push_back(edges);
                }

            for (size_t j = 0; j < bccs.size(); ++j)
            {
                vector<int> spanning_tree;
                for (size_t k = 0; k < bccs.size(); ++k)
                {
                    spanning_tree.insert(spanning_tree.end(), bcc_trees[k].begin(), bcc_trees[k].end());
                    if (k != j)
                        spanning_tree.push_back(edge_to_bcc[k]);
                }

                for (auto const &x : bccs[j])
                    if (adj[i][x] != -1)
                    {
                        spanning_tree.push_back(adj[i][x]);
                        break;
                    }

                int in_overlap = count_common_roads(spanning_tree), out_overlap = in_overlap;
                vector<int> in;
                bool skipped = 0, know_in = 0;
                for (auto const &x : bccs[j])
                    if (adj[i][x] != -1)
                    {
                        if (!skipped)
                        {
                            checked[adj[i][x]] = 1;
                            in.push_back(adj[i][x]);
                            skipped = 1;
                            continue;
                        }

                        if (checked[adj[i][x]] && know_in)
                            continue;

                        spanning_tree.pop_back();
                        spanning_tree.push_back(adj[i][x]);
                        int y = count_common_roads(spanning_tree);
                        if (!know_in)
                        {
                            if (checked[adj[i][x]])
                            {
                                know_in = 1;
                                if (is_in[adj[i][x]])
                                {
                                    if (in_overlap < y)
                                        in.clear(), ++in_overlap;
                                    else
                                        --out_overlap;
                                }
                                else
                                {
                                    if (in_overlap == y)
                                        in.clear(), ++in_overlap;
                                    else
                                        --out_overlap;
                                }
                            }
                            if (y == in_overlap)
                                in.push_back(adj[i][x]);
                            else if (y < in_overlap)
                            {
                                out_overlap--;
                                know_in = 1;
                            }
                            else if (y > in_overlap)
                            {
                                know_in = 1;
                                in.clear();
                                in_overlap++;
                                in.push_back(adj[i][x]);
                            }
                        }
                        else if (y == in_overlap)
                            in.push_back(adj[i][x]);

                        checked[adj[i][x]] = 1;
                    }

                ans.insert(ans.end(), in.begin(), in.end());
                for (auto const &j : in)
                    is_in[j] = 1;
            }
        }

        sort(ans.begin(), ans.end());
        ans.resize(unique(ans.begin(), ans.end()) - ans.begin());
        return ans;
    }
};

template <size_t N>
struct dsu
{
    int p[N];

    int repr(int u) { return p[u] < 0 ? u : p[u] = repr(p[u]); }

    bool merge(int u, int v)
    {
        u = repr(u), v = repr(v);
        if (u == v)
            return 0;
        if (p[u] > p[v])
            swap(u, v);
        p[u] += p[v];
        p[v] = u;
        return 1;
    }

    int set_size(int u) { return -p[repr(u)]; }

    void reset() { memset(p, 255, sizeof p); }
};

namespace nlogn
{
    constexpr size_t N = 500;

    int adj[N][N], degree[N];
    bitset<N *(N - 1) / 2> is_in, removed;
    dsu<N> d;

    vector<int> solve(int n, vector<int> u, vector<int> v)
    {
        for (int i = 0; i < u.size(); ++i)
            adj[u[i]][v[i]] = adj[v[i]][u[i]] = i;

        auto query_forest = [&](vector<int> forest)
        {
            d.reset();
            for (int i : forest)
                d.merge(u[i], v[i]);
            int ans = 0;
            for (int i = 0; i + 1 < n; ++i)
                if (d.merge(i, i + 1) && is_in[adj[i][i + 1]])
                    --ans, forest.push_back(adj[i][i + 1]);
            return count_common_roads(forest);
        };

        auto check_edge = [&](int u, int v)
        {
            int w = 0;
            while (w == u || w == v)
                ++w;
            vector<int> spanning_tree;
            for (int i = 0; i < n; ++i)
                if (i != u && i != v && i != w)
                    spanning_tree.push_back(adj[u][i]);

            spanning_tree.push_back(adj[u][v]);
            spanning_tree.push_back(adj[v][w]);
            int a = count_common_roads(spanning_tree);
            spanning_tree[spanning_tree.size() - 2] = adj[w][u];
            int b = count_common_roads(spanning_tree);
            spanning_tree[spanning_tree.size() - 1] = adj[u][v];
            int c = count_common_roads(spanning_tree);
            return max(a, c) > b;
        };

        for (int i = 0; i + 1 < n; ++i)
            is_in[adj[i][i + 1]] = check_edge(i, i + 1);
        for (int i = 0; i < n; ++i)
        {
            vector<int> spanning_tree;
            for (int j = 0; j < n; ++j)
                if (i != j)
                    spanning_tree.push_back(adj[i][j]);
            degree[i] = count_common_roads(spanning_tree);
        }

        queue<int> q;
        for (int i = 0; i < n; ++i)
            if (degree[i] == 1)
                q.push(i);

        vector<int> ans;
        while (!q.empty())
        {
            int x = q.front();
            q.pop();

            int a = 0, b = n - 1;
            while (a < b)
            {
                int mid = (a + b) / 2;
                vector<int> forest;
                for (int j = 0; j <= mid; ++j)
                    if (j != x && !removed[adj[x][j]])
                        forest.push_back(adj[x][j]);
                if (query_forest(forest))
                    b = mid;
                else
                    a = mid + 1;
            }

            removed[adj[x][a]] = 1;
            ans.push_back(adj[a][x]);

            degree[a]--;
            if (degree[a] == 1)
                q.push(a);
        }

        return ans;
    }
};

vector<int> find_roads(int n, vector<int> u, vector<int> v)
{
    if (n <= 240)
        return quadratic::solve(n, u, v);
    else
        return nlogn::solve(n, u, v);
}

Compilation message

simurgh.cpp: In function 'std::vector<int> quadratic::solve(int, std::vector<int>, std::vector<int>)':
simurgh.cpp:16:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   16 |         for (int i = 0; i < u.size(); ++i)
      |                         ~~^~~~~~~~~~
simurgh.cpp: In function 'std::vector<int> nlogn::solve(int, std::vector<int>, std::vector<int>)':
simurgh.cpp:177:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  177 |         for (int i = 0; i < u.size(); ++i)
      |                         ~~^~~~~~~~~~

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 468 KB correct
2 Correct 1 ms 468 KB correct
3 Correct 1 ms 436 KB correct
4 Correct 1 ms 468 KB correct
5 Correct 1 ms 468 KB correct
6 Correct 1 ms 436 KB correct
7 Correct 0 ms 468 KB correct
8 Correct 1 ms 468 KB correct
9 Correct 1 ms 468 KB correct
10 Correct 1 ms 436 KB correct
11 Correct 1 ms 440 KB correct
12 Correct 1 ms 468 KB correct
13 Correct 1 ms 468 KB correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 468 KB correct
2 Correct 1 ms 468 KB correct
3 Correct 1 ms 436 KB correct
4 Correct 1 ms 468 KB correct
5 Correct 1 ms 468 KB correct
6 Correct 1 ms 436 KB correct
7 Correct 0 ms 468 KB correct
8 Correct 1 ms 468 KB correct
9 Correct 1 ms 468 KB correct
10 Correct 1 ms 436 KB correct
11 Correct 1 ms 440 KB correct
12 Correct 1 ms 468 KB correct
13 Correct 1 ms 468 KB correct
14 Correct 1 ms 596 KB correct
15 Correct 2 ms 572 KB correct
16 Correct 1 ms 596 KB correct
17 Correct 1 ms 568 KB correct
18 Correct 1 ms 468 KB correct
19 Correct 2 ms 596 KB correct
20 Correct 1 ms 596 KB correct
21 Correct 1 ms 568 KB correct
22 Correct 1 ms 596 KB correct
23 Correct 1 ms 468 KB correct
24 Correct 1 ms 468 KB correct
25 Correct 1 ms 468 KB correct
26 Correct 1 ms 468 KB correct
27 Correct 1 ms 468 KB correct
28 Correct 1 ms 436 KB correct
29 Correct 1 ms 468 KB correct
30 Correct 1 ms 468 KB correct
31 Correct 1 ms 468 KB correct
32 Correct 1 ms 568 KB correct
33 Correct 1 ms 468 KB correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 468 KB correct
2 Correct 1 ms 468 KB correct
3 Correct 1 ms 436 KB correct
4 Correct 1 ms 468 KB correct
5 Correct 1 ms 468 KB correct
6 Correct 1 ms 436 KB correct
7 Correct 0 ms 468 KB correct
8 Correct 1 ms 468 KB correct
9 Correct 1 ms 468 KB correct
10 Correct 1 ms 436 KB correct
11 Correct 1 ms 440 KB correct
12 Correct 1 ms 468 KB correct
13 Correct 1 ms 468 KB correct
14 Correct 1 ms 596 KB correct
15 Correct 2 ms 572 KB correct
16 Correct 1 ms 596 KB correct
17 Correct 1 ms 568 KB correct
18 Correct 1 ms 468 KB correct
19 Correct 2 ms 596 KB correct
20 Correct 1 ms 596 KB correct
21 Correct 1 ms 568 KB correct
22 Correct 1 ms 596 KB correct
23 Correct 1 ms 468 KB correct
24 Correct 1 ms 468 KB correct
25 Correct 1 ms 468 KB correct
26 Correct 1 ms 468 KB correct
27 Correct 1 ms 468 KB correct
28 Correct 1 ms 436 KB correct
29 Correct 1 ms 468 KB correct
30 Correct 1 ms 468 KB correct
31 Correct 1 ms 468 KB correct
32 Correct 1 ms 568 KB correct
33 Correct 1 ms 468 KB correct
34 Correct 87 ms 1984 KB correct
35 Correct 89 ms 1940 KB correct
36 Correct 60 ms 1620 KB correct
37 Correct 7 ms 628 KB correct
38 Correct 89 ms 1972 KB correct
39 Correct 75 ms 1844 KB correct
40 Correct 60 ms 1616 KB correct
41 Correct 92 ms 1988 KB correct
42 Correct 86 ms 1876 KB correct
43 Correct 46 ms 1428 KB correct
44 Correct 38 ms 1108 KB correct
45 Correct 43 ms 1236 KB correct
46 Correct 33 ms 1108 KB correct
47 Correct 16 ms 852 KB correct
48 Correct 4 ms 596 KB correct
49 Correct 6 ms 580 KB correct
50 Correct 16 ms 840 KB correct
51 Correct 45 ms 1236 KB correct
52 Correct 46 ms 1172 KB correct
53 Correct 38 ms 1092 KB correct
54 Correct 46 ms 1364 KB correct
55 Correct 44 ms 1236 KB correct
56 Correct 44 ms 1236 KB correct
57 Correct 49 ms 1264 KB correct

Subtask #4
0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 468 KB correct
2 Correct 1 ms 468 KB correct
3 Incorrect 25 ms 3384 KB WA in grader: NO
4 Halted 0 ms 0 KB -

Subtask #5
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 468 KB correct
2 Correct 1 ms 468 KB correct
3 Correct 1 ms 436 KB correct
4 Correct 1 ms 468 KB correct
5 Correct 1 ms 468 KB correct
6 Correct 1 ms 436 KB correct
7 Correct 0 ms 468 KB correct
8 Correct 1 ms 468 KB correct
9 Correct 1 ms 468 KB correct
10 Correct 1 ms 436 KB correct
11 Correct 1 ms 440 KB correct
12 Correct 1 ms 468 KB correct
13 Correct 1 ms 468 KB correct
14 Correct 1 ms 596 KB correct
15 Correct 2 ms 572 KB correct
16 Correct 1 ms 596 KB correct
17 Correct 1 ms 568 KB correct
18 Correct 1 ms 468 KB correct
19 Correct 2 ms 596 KB correct
20 Correct 1 ms 596 KB correct
21 Correct 1 ms 568 KB correct
22 Correct 1 ms 596 KB correct
23 Correct 1 ms 468 KB correct
24 Correct 1 ms 468 KB correct
25 Correct 1 ms 468 KB correct
26 Correct 1 ms 468 KB correct
27 Correct 1 ms 468 KB correct
28 Correct 1 ms 436 KB correct
29 Correct 1 ms 468 KB correct
30 Correct 1 ms 468 KB correct
31 Correct 1 ms 468 KB correct
32 Correct 1 ms 568 KB correct
33 Correct 1 ms 468 KB correct
34 Correct 87 ms 1984 KB correct
35 Correct 89 ms 1940 KB correct
36 Correct 60 ms 1620 KB correct
37 Correct 7 ms 628 KB correct
38 Correct 89 ms 1972 KB correct
39 Correct 75 ms 1844 KB correct
40 Correct 60 ms 1616 KB correct
41 Correct 92 ms 1988 KB correct
42 Correct 86 ms 1876 KB correct
43 Correct 46 ms 1428 KB correct
44 Correct 38 ms 1108 KB correct
45 Correct 43 ms 1236 KB correct
46 Correct 33 ms 1108 KB correct
47 Correct 16 ms 852 KB correct
48 Correct 4 ms 596 KB correct
49 Correct 6 ms 580 KB correct
50 Correct 16 ms 840 KB correct
51 Correct 45 ms 1236 KB correct
52 Correct 46 ms 1172 KB correct
53 Correct 38 ms 1092 KB correct
54 Correct 46 ms 1364 KB correct
55 Correct 44 ms 1236 KB correct
56 Correct 44 ms 1236 KB correct
57 Correct 49 ms 1264 KB correct
58 Correct 0 ms 468 KB correct
59 Correct 1 ms 468 KB correct
60 Incorrect 25 ms 3384 KB WA in grader: NO
61 Halted 0 ms 0 KB -