Submission #1099584

# Submission time Handle Problem Language Result Execution time Memory
1099584 2024-10-11T18:06:58 Z onbert Meetings 2 (JOI21_meetings2) C++17
100 / 100
628 ms 41956 KB
#include <bits/stdc++.h>
using namespace std;
#define int long long
const int maxn = 2e5 + 5, lg = 20;
int N;
vector<int> adj[maxn];
int ans[maxn];

bool vis[maxn];
int FA[maxn], D[maxn], SZ[maxn];
void DFS(int u) {
    vis[u] = true;
    SZ[u] = 1;
    for (int v:adj[u]) if (!vis[v]) {
        FA[v] = u, D[v] = u;
        DFS(v);
        SZ[u] += SZ[v];
    }
}

int fa[maxn], grp[maxn], sz[maxn], d[maxn];
vector<int> node;
void dfs0(int u) {
    vis[u] = true;
    node.push_back(u);
    sz[u] = 1;
    bool ok = false;
    for (int v:adj[u]) if (!vis[v]) {
        dfs0(v);
        sz[u] += sz[v];
    }
}
void dfs1(int u, int anc) {
    vis[u] = true;
    grp[u] = anc;
    for (int v:adj[u]) if (!vis[v]) {
        fa[v] = u, d[v] = d[u] + 1;
        dfs1(v, anc);
    }
}

void centroid(int start) {
    node.clear();
    dfs0(start);
    int n = node.size();
    int cent = -1;
    for (int i:node) {
        bool ok = (n - sz[i] <= n/2);
        // cout << i << endl;
        // cout << n - sz[i] << " ";
        for (int j:adj[i]) if (sz[j] < sz[i]) {
            // cout << j << '.' << sz[j] << " ";
            if (sz[j] > n/2) ok = false;
        }
        // cout << endl;
        if (ok) cent = i;
    }
    // cout << cent << endl;
    for (int i:node) vis[i] = false;
    vis[cent] = true, fa[cent] = -1, grp[cent] = -1, d[cent] = 0;
    for (int i:adj[cent]) {
        fa[i] = cent;
        d[i] = 1;
        dfs1(i, i);
    }
    vector<pair<int,int>> vec;
    for (int i:node) if (i!=cent) {
        // if (i==5) cout << "test " << fa[i] << " " << FA[i] << endl;
        if (fa[i] == FA[i]) vec.push_back({SZ[i], i});
        else vec.push_back({N - SZ[fa[i]], i});
    }
    sort(vec.rbegin(), vec.rend());
    pair<int,int> mx1 = {0, cent}, mx2 = {0, cent};
    for (auto [val, u]:vec) {
        // cout << u << " " << val << " " << d[u] << " " << grp[u] << endl;
        if (mx1.second!=grp[u]) ans[val] = max(mx1.first + d[u] + 1, ans[val]);
        else ans[val] = max(mx2.first + d[u] + 1, ans[val]);

        // if (mx1.second!=grp[u]) cout << mx1.first + d[u] + 1 << endl;
        // else cout << mx2.first + d[u] + 1 << endl;
        
        if (mx1.second == grp[u]) mx1.first = max(d[u], mx1.first);
        else if (mx2.second == grp[u]) mx2.first = max(d[u], mx2.first);
        else if (d[u] > mx2.first) mx2 = {d[u], grp[u]};
        if (mx1.first < mx2.first) swap(mx1, mx2);
    }
    for (int i:node) vis[i] = false;
    for (int i:adj[cent]) {
        adj[i].erase(find(adj[i].begin(), adj[i].end(), cent));
        centroid(i);
    }
}

signed main() {
    ios::sync_with_stdio(0); cin.tie(0);
    cin >> N;
    for (int i=1;i<=N-1;i++) {
        int u, v;
        cin >> u >> v;
        adj[u].push_back(v);
        adj[v].push_back(u);
    }
    D[1] = 0, FA[1] = -1;
    DFS(1);

    for (int i=1;i<=N;i++) ans[i] = 1;

    for (int i=1;i<=N;i++) vis[i] = 0;
    centroid(1);

    for (int i=N/2-1;i>=1;i--) ans[i] = max(ans[i], ans[i+1]);
    for (int i=1;i<=N;i++) {
        if (i%2==0) cout << ans[i/2] << endl;
        else cout << "1\n";
    }
}

Compilation message

meetings2.cpp: In function 'void dfs0(long long int)':
meetings2.cpp:27:10: warning: unused variable 'ok' [-Wunused-variable]
   27 |     bool ok = false;
      |          ^~
# Verdict Execution time Memory Grader output
1 Correct 3 ms 5212 KB Output is correct
2 Correct 2 ms 5212 KB Output is correct
3 Correct 2 ms 5212 KB Output is correct
4 Correct 3 ms 5212 KB Output is correct
5 Correct 2 ms 5208 KB Output is correct
6 Correct 2 ms 5212 KB Output is correct
7 Correct 2 ms 5124 KB Output is correct
8 Correct 2 ms 5212 KB Output is correct
9 Correct 2 ms 5212 KB Output is correct
10 Correct 3 ms 5212 KB Output is correct
11 Correct 2 ms 5212 KB Output is correct
12 Correct 2 ms 5164 KB Output is correct
13 Correct 2 ms 5164 KB Output is correct
14 Correct 2 ms 5212 KB Output is correct
15 Correct 3 ms 5212 KB Output is correct
16 Correct 2 ms 5212 KB Output is correct
17 Correct 2 ms 5212 KB Output is correct
18 Correct 2 ms 5124 KB Output is correct
19 Correct 2 ms 5212 KB Output is correct
20 Correct 2 ms 5212 KB Output is correct
21 Correct 2 ms 5212 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 5212 KB Output is correct
2 Correct 2 ms 5212 KB Output is correct
3 Correct 2 ms 5212 KB Output is correct
4 Correct 3 ms 5212 KB Output is correct
5 Correct 2 ms 5208 KB Output is correct
6 Correct 2 ms 5212 KB Output is correct
7 Correct 2 ms 5124 KB Output is correct
8 Correct 2 ms 5212 KB Output is correct
9 Correct 2 ms 5212 KB Output is correct
10 Correct 3 ms 5212 KB Output is correct
11 Correct 2 ms 5212 KB Output is correct
12 Correct 2 ms 5164 KB Output is correct
13 Correct 2 ms 5164 KB Output is correct
14 Correct 2 ms 5212 KB Output is correct
15 Correct 3 ms 5212 KB Output is correct
16 Correct 2 ms 5212 KB Output is correct
17 Correct 2 ms 5212 KB Output is correct
18 Correct 2 ms 5124 KB Output is correct
19 Correct 2 ms 5212 KB Output is correct
20 Correct 2 ms 5212 KB Output is correct
21 Correct 2 ms 5212 KB Output is correct
22 Correct 8 ms 5724 KB Output is correct
23 Correct 7 ms 5684 KB Output is correct
24 Correct 9 ms 5724 KB Output is correct
25 Correct 7 ms 5724 KB Output is correct
26 Correct 7 ms 5680 KB Output is correct
27 Correct 7 ms 5688 KB Output is correct
28 Correct 8 ms 5800 KB Output is correct
29 Correct 8 ms 5724 KB Output is correct
30 Correct 7 ms 5976 KB Output is correct
31 Correct 7 ms 5724 KB Output is correct
32 Correct 8 ms 5912 KB Output is correct
33 Correct 7 ms 5724 KB Output is correct
34 Correct 6 ms 5724 KB Output is correct
35 Correct 5 ms 5684 KB Output is correct
36 Correct 7 ms 5720 KB Output is correct
37 Correct 5 ms 5724 KB Output is correct
38 Correct 6 ms 5880 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 5212 KB Output is correct
2 Correct 2 ms 5212 KB Output is correct
3 Correct 2 ms 5212 KB Output is correct
4 Correct 3 ms 5212 KB Output is correct
5 Correct 2 ms 5208 KB Output is correct
6 Correct 2 ms 5212 KB Output is correct
7 Correct 2 ms 5124 KB Output is correct
8 Correct 2 ms 5212 KB Output is correct
9 Correct 2 ms 5212 KB Output is correct
10 Correct 3 ms 5212 KB Output is correct
11 Correct 2 ms 5212 KB Output is correct
12 Correct 2 ms 5164 KB Output is correct
13 Correct 2 ms 5164 KB Output is correct
14 Correct 2 ms 5212 KB Output is correct
15 Correct 3 ms 5212 KB Output is correct
16 Correct 2 ms 5212 KB Output is correct
17 Correct 2 ms 5212 KB Output is correct
18 Correct 2 ms 5124 KB Output is correct
19 Correct 2 ms 5212 KB Output is correct
20 Correct 2 ms 5212 KB Output is correct
21 Correct 2 ms 5212 KB Output is correct
22 Correct 8 ms 5724 KB Output is correct
23 Correct 7 ms 5684 KB Output is correct
24 Correct 9 ms 5724 KB Output is correct
25 Correct 7 ms 5724 KB Output is correct
26 Correct 7 ms 5680 KB Output is correct
27 Correct 7 ms 5688 KB Output is correct
28 Correct 8 ms 5800 KB Output is correct
29 Correct 8 ms 5724 KB Output is correct
30 Correct 7 ms 5976 KB Output is correct
31 Correct 7 ms 5724 KB Output is correct
32 Correct 8 ms 5912 KB Output is correct
33 Correct 7 ms 5724 KB Output is correct
34 Correct 6 ms 5724 KB Output is correct
35 Correct 5 ms 5684 KB Output is correct
36 Correct 7 ms 5720 KB Output is correct
37 Correct 5 ms 5724 KB Output is correct
38 Correct 6 ms 5880 KB Output is correct
39 Correct 429 ms 35396 KB Output is correct
40 Correct 404 ms 34868 KB Output is correct
41 Correct 420 ms 35384 KB Output is correct
42 Correct 415 ms 35892 KB Output is correct
43 Correct 465 ms 35908 KB Output is correct
44 Correct 448 ms 35740 KB Output is correct
45 Correct 628 ms 39556 KB Output is correct
46 Correct 511 ms 41956 KB Output is correct
47 Correct 215 ms 33472 KB Output is correct
48 Correct 183 ms 33888 KB Output is correct
49 Correct 455 ms 36152 KB Output is correct
50 Correct 220 ms 36340 KB Output is correct
51 Correct 352 ms 41660 KB Output is correct