제출 #1344332

#제출 시각아이디문제언어결과실행 시간메모리
1344332avighnaMeetings 2 (JOI21_meetings2)C++20
100 / 100
496 ms56320 KiB
#include <bits/stdc++.h>

using namespace std;

int main() {
  cin.tie(nullptr)->sync_with_stdio(false);

  int n;
  cin >> n;
  vector<vector<int>> adj(n + 1);
  for (int i = 0, u, v; i < n - 1; ++i) {
    cin >> u >> v;
    adj[u].push_back(v);
    adj[v].push_back(u);
  }

  vector<pair<int, pair<int, int>>> edges;
  vector lift(n + 1, vector<int>(20));
  vector<int> subtree_size(n + 1), dep(n + 1);
  auto dfs = [&](auto &&self, int u, int p, int d) -> void {
    dep[u] = d;
    subtree_size[u] = 1;
    for (int &i : adj[u]) {
      if (i == p) {
        continue;
      }
      lift[i][0] = u;
      self(self, i, u, d + 1);
      edges.push_back({min(subtree_size[i], n - subtree_size[i]), {u, i}});
      subtree_size[u] += subtree_size[i];
    }
  };
  lift[1][0] = 1;
  dfs(dfs, 1, 0, 0);
  sort(edges.begin(), edges.end());

  for (int bt = 1; bt < 20; ++bt) {
    for (int i = 1; i <= n; ++i) {
      lift[i][bt] = lift[lift[i][bt - 1]][bt - 1];
    }
  }

  auto lca = [&](int u, int v) {
    if (dep[u] < dep[v]) {
      swap(u, v);
    }
    int k = dep[u] - dep[v];
    for (int bt = 0; bt < 20; ++bt) {
      if (k & 1 << bt) {
        u = lift[u][bt];
      }
    }
    if (u == v) {
      return u;
    }
    for (int bt = 19; bt >= 0; --bt) {
      if (lift[u][bt] != lift[v][bt]) {
        u = lift[u][bt], v = lift[v][bt];
      }
    }
    return lift[u][0];
  };
  auto dist = [&](int u, int v) { return dep[u] + dep[v] - 2 * dep[lca(u, v)]; };

  vector<int> par(n + 1);
  iota(par.begin(), par.end(), 0);
  vector<pair<int, int>> diam(n + 1);
  int diam_len = 0;
  for (int i = 1; i <= n; ++i) {
    diam[i] = {i, i};
  }

  auto _root = [&](auto &&self, int u) -> int { return u == par[u] ? u : par[u] = self(self, par[u]); };
  auto root = [&](int u) { return _root(_root, u); };
  auto merge = [&](int u, int v) {
    u = root(u), v = root(v);
    if (u == v) {
      return;
    }
    par[v] = u;
    auto check = [&](int x, int y) {
      int d = dist(x, y);
      if (d > dist(diam[u].first, diam[u].second)) {
        diam[u] = {x, y};
        diam_len = d;
      }
    };
    auto [p, q] = diam[u];
    auto [r, s] = diam[v];
    check(p, r);
    check(p, s);
    check(q, r);
    check(q, s);
    check(r, s);
  };

  vector<int> ans(n / 2 + 1);
  for (int s = n / 2; s >= 1; --s) {
    while (!edges.empty() && edges.back().first >= s) {
      auto [u, v] = edges.back().second;
      edges.pop_back();
      merge(u, v);
    }
    ans[s] = diam_len + 1;
  }

  for (int i = 1; i <= n; ++i) {
    if (i & 1) {
      cout << "1\n";
    } else {
      cout << ans[i >> 1] << '\n';
    }
  }
}
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