oj.uz

Submission #464967

# Submission time Handle Problem Language Result Execution time Memory
464967 2021-08-14T16:20:12 Z blue Meetings 2 (JOI21_meetings2) C++17
100 / 100
 832 ms 53324 KB 
#include <iostream>
#include <vector>
#include <queue>
#include <set>
using namespace std;

const int maxN = 200'000;
const int logN = 19;

int N;
vector<int> edge[1+maxN];

int anc[1+maxN][1+logN];
vector<int> depth(1+maxN);

void dfs(int u)
{
    for(int v: edge[u])
    {
        if(anc[u][0] == v) continue;
        anc[v][0] = u;
        depth[v] = depth[u] + 1;
        dfs(v);
    }
}

int lca(int u, int v)
{
    if(depth[u] > depth[v]) swap(u, v);
    for(int e = logN; e >= 0; e--)
    {
        if(depth[ anc[v][e] ] >= depth[u])
            v = anc[v][e];
    }
    if(u == v) return u;

    for(int e = logN; e >= 0; e--)
    {
        if(anc[u][e] == anc[v][e]) continue;
        u = anc[u][e];
        v = anc[v][e];
    }

    u = anc[u][0];
    return u;
}

int dist(int u, int v)
{
    return depth[u] + depth[v] - 2*depth[lca(u, v)];
}






int main()
{
    cin >> N;
    for(int e = 1; e <= N-1; e++)
    {
        int A, B;
        cin >> A >> B;
        edge[A].push_back(B);
        edge[B].push_back(A);
    }

    anc[1][0] = anc[0][0] = 0;
    depth[1] = 1;
    dfs(1);




    for(int e = 1; e <= logN; e++)
    {
        for(int u = 0; u <= N; u++)
        {
            anc[u][e] = anc[ anc[u][e-1] ][e-1];
        }
    }

    vector<int> added(N+1, 0); //add time
    int add_id = 0;

    vector<int> counter(N+1, 0);
    vector<int> leaf_size(1+N, 1);
    set<int> tbv[1+N];
    int visit_count = 0;

    for(int u = 1; u <= N; u++)
    {
        if(edge[u].size() == 1)
        {
            tbv[1].insert(u);
            added[u] = 1;
        }
    }

    vector<int> suspicious;

    for(int s = 1; s <= N; s++)
    {
        for(int u: tbv[s])
        {
            bool flag = 0;
            for(int v: edge[u])
            {
                if(added[v]) continue;
                flag = 1;

                leaf_size[v] += leaf_size[u];
                counter[v]++;

                if(counter[v] == edge[v].size() - 1)
                {
                    // cerr << "adding " << v << " from " << u << '\n';
                    add_id++;
                    added[v] = add_id;
                    tbv[leaf_size[v]].insert(v);
                }
            }
            if(flag == 0)
                suspicious.push_back(u);
        }
    }

    // for(int s:suspicious) cerr << s << ' ' << leaf_size[s] << '\n';
    // cerr << '\n';

    // cerr << suspicious.size() << '\n';

    if(suspicious.size() == 1)
    {
        int u = suspicious[0];
        int max_add = -1;
        for(int v: edge[u])
        {
            if(max_add == -1 || added[v] > added[max_add])
                max_add = v;
        }

        tbv[leaf_size[max_add]].erase(max_add);
        leaf_size[max_add] += leaf_size[u];
        tbv[leaf_size[max_add]].insert(max_add);
    }

    // for(int s = 1; s <= N; s++)
    // {
    //     cerr << "s = " << s << ": ";
    //     for(int u: tbv[s]) cerr << u << ' ';
    //     cerr << '\n';
    // }

    vector<int> res(N+1, 1);

    int curr1 = -1, curr2 = -1;
    int J = N/2;

    for(int s = N; s >= 1; s--)
    {
        for(int u: tbv[s])
        {
            // cerr << "adding " << u << '\n';
            if(curr1 == -1)
                curr1 = u;
            else if(curr2 == -1)
                curr2 = u;
            else
            {
                // cerr << dist(u, curr1) << ' ' << dist(u, curr2) << ' ' << dist(curr1, curr2) << '\n';
                if(dist(u, curr1) > dist(curr1, curr2))
                {
                    // cerr << "entered 1\n";
                    curr2 = u;
                }
                else if(dist(u, curr2) > dist(curr1, curr2))
                {
                    // cerr << "entered 2\n";
                    curr1 = u;
                }
            }

            if(curr1 == -1 || curr2 == -1) continue;
            // cerr << "diameter = " << curr1 << ' ' << curr2 << '\n';
            // cerr << "min leaf size = " << min(leaf_size[curr1], leaf_size[curr2]) << ' ' << dist(curr1, curr2) + 1 << '\n';
            //
            // cerr << "J = " << J << '\n';

            while(J > min(leaf_size[curr1], leaf_size[curr2]))
            {
                J--;
                // cerr << "j--\n";
            }

            if(J == min(leaf_size[curr1], leaf_size[curr2]))
            {
                res[2*J] = dist(curr1, curr2) + 1;
            }
        }
    }

    for(int q = 2*(N/2) - 2; q >= 2; q -= 2)
        res[q] = max(res[q], res[q+2]);

    for(int i = 1; i <= N; i++) cout << res[i] << ' ';
    cout << '\n';
}

Compilation message

meetings2.cpp: In function 'int main()':
meetings2.cpp:116:31: warning: comparison of integer expressions of different signedness: '__gnu_cxx::__alloc_traits<std::allocator<int>, int>::value_type' {aka 'int'} and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  116 |                 if(counter[v] == edge[v].size() - 1)
meetings2.cpp:90:9: warning: unused variable 'visit_count' [-Wunused-variable]
   90 |     int visit_count = 0;
      |         ^~~~~~~~~~~

Subtask #1
4.0 / 4.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 5708 KB Output is correct
2 Correct 3 ms 5708 KB Output is correct
3 Correct 3 ms 5708 KB Output is correct
4 Correct 4 ms 5708 KB Output is correct
5 Correct 4 ms 5708 KB Output is correct
6 Correct 4 ms 5768 KB Output is correct
7 Correct 4 ms 5708 KB Output is correct
8 Correct 5 ms 5672 KB Output is correct
9 Correct 4 ms 5708 KB Output is correct
10 Correct 4 ms 5708 KB Output is correct
11 Correct 4 ms 5708 KB Output is correct
12 Correct 4 ms 5708 KB Output is correct
13 Correct 4 ms 5708 KB Output is correct
14 Correct 4 ms 5672 KB Output is correct
15 Correct 4 ms 5708 KB Output is correct
16 Correct 3 ms 5708 KB Output is correct
17 Correct 4 ms 5708 KB Output is correct
18 Correct 4 ms 5708 KB Output is correct
19 Correct 3 ms 5708 KB Output is correct
20 Correct 4 ms 5708 KB Output is correct
21 Correct 4 ms 5708 KB Output is correct

Subtask #2
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 5708 KB Output is correct
2 Correct 3 ms 5708 KB Output is correct
3 Correct 3 ms 5708 KB Output is correct
4 Correct 4 ms 5708 KB Output is correct
5 Correct 4 ms 5708 KB Output is correct
6 Correct 4 ms 5768 KB Output is correct
7 Correct 4 ms 5708 KB Output is correct
8 Correct 5 ms 5672 KB Output is correct
9 Correct 4 ms 5708 KB Output is correct
10 Correct 4 ms 5708 KB Output is correct
11 Correct 4 ms 5708 KB Output is correct
12 Correct 4 ms 5708 KB Output is correct
13 Correct 4 ms 5708 KB Output is correct
14 Correct 4 ms 5672 KB Output is correct
15 Correct 4 ms 5708 KB Output is correct
16 Correct 3 ms 5708 KB Output is correct
17 Correct 4 ms 5708 KB Output is correct
18 Correct 4 ms 5708 KB Output is correct
19 Correct 3 ms 5708 KB Output is correct
20 Correct 4 ms 5708 KB Output is correct
21 Correct 4 ms 5708 KB Output is correct
22 Correct 11 ms 6604 KB Output is correct
23 Correct 11 ms 6688 KB Output is correct
24 Correct 12 ms 6704 KB Output is correct
25 Correct 14 ms 6696 KB Output is correct
26 Correct 15 ms 6604 KB Output is correct
27 Correct 12 ms 6604 KB Output is correct
28 Correct 12 ms 6604 KB Output is correct
29 Correct 12 ms 6704 KB Output is correct
30 Correct 13 ms 6604 KB Output is correct
31 Correct 13 ms 6604 KB Output is correct
32 Correct 12 ms 6728 KB Output is correct
33 Correct 12 ms 6604 KB Output is correct
34 Correct 12 ms 6712 KB Output is correct
35 Correct 13 ms 6604 KB Output is correct
36 Correct 4 ms 6700 KB Output is correct
37 Correct 11 ms 6720 KB Output is correct
38 Correct 11 ms 6696 KB Output is correct

Subtask #3
80.0 / 80.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 5708 KB Output is correct
2 Correct 3 ms 5708 KB Output is correct
3 Correct 3 ms 5708 KB Output is correct
4 Correct 4 ms 5708 KB Output is correct
5 Correct 4 ms 5708 KB Output is correct
6 Correct 4 ms 5768 KB Output is correct
7 Correct 4 ms 5708 KB Output is correct
8 Correct 5 ms 5672 KB Output is correct
9 Correct 4 ms 5708 KB Output is correct
10 Correct 4 ms 5708 KB Output is correct
11 Correct 4 ms 5708 KB Output is correct
12 Correct 4 ms 5708 KB Output is correct
13 Correct 4 ms 5708 KB Output is correct
14 Correct 4 ms 5672 KB Output is correct
15 Correct 4 ms 5708 KB Output is correct
16 Correct 3 ms 5708 KB Output is correct
17 Correct 4 ms 5708 KB Output is correct
18 Correct 4 ms 5708 KB Output is correct
19 Correct 3 ms 5708 KB Output is correct
20 Correct 4 ms 5708 KB Output is correct
21 Correct 4 ms 5708 KB Output is correct
22 Correct 11 ms 6604 KB Output is correct
23 Correct 11 ms 6688 KB Output is correct
24 Correct 12 ms 6704 KB Output is correct
25 Correct 14 ms 6696 KB Output is correct
26 Correct 15 ms 6604 KB Output is correct
27 Correct 12 ms 6604 KB Output is correct
28 Correct 12 ms 6604 KB Output is correct
29 Correct 12 ms 6704 KB Output is correct
30 Correct 13 ms 6604 KB Output is correct
31 Correct 13 ms 6604 KB Output is correct
32 Correct 12 ms 6728 KB Output is correct
33 Correct 12 ms 6604 KB Output is correct
34 Correct 12 ms 6712 KB Output is correct
35 Correct 13 ms 6604 KB Output is correct
36 Correct 4 ms 6700 KB Output is correct
37 Correct 11 ms 6720 KB Output is correct
38 Correct 11 ms 6696 KB Output is correct
39 Correct 688 ms 51772 KB Output is correct
40 Correct 575 ms 51004 KB Output is correct
41 Correct 622 ms 51936 KB Output is correct
42 Correct 643 ms 52756 KB Output is correct
43 Correct 622 ms 52728 KB Output is correct
44 Correct 627 ms 52676 KB Output is correct
45 Correct 832 ms 52920 KB Output is correct
46 Correct 608 ms 52932 KB Output is correct
47 Correct 529 ms 53112 KB Output is correct
48 Correct 442 ms 53236 KB Output is correct
49 Correct 630 ms 53264 KB Output is correct
50 Correct 501 ms 53324 KB Output is correct
51 Correct 536 ms 53072 KB Output is correct