Submission #721765

#	Time	Username	Problem	Language	Result	Execution time	Memory
721765		viwlesxq	Easter Eggs (info1cup17_eastereggs)	C++17	Compilation error	0 ms	0 KiB

eastereggs

#include <bits/stdc++.h>

using namespace std;

typedef int64_t ll;
typedef string str;

int findEgg(int n, vector <pair <int, int>> edges) {
  vector <int> g[n + 1];
  int par[n + 1], sz[n + 1];
  vector <bool> used(n + 1, false);
  for (auto [a, b] : edges) {
    g[a].push_back(b);
    g[b].push_back(a);
  }
  function <void(int, int)> prepare = [&](int v, int p) {
    par[v] = p;
    sz[v] = 1;
    for (int to : g[v]) {
      if (to == p) {
        continue;
      }
      prepare(to, v);
      sz[v] += sz[to];
    }
  };
  prepare(1, -1);
  function <int(int, int)> get_centroid = [&](int v, int p) {
    for (int to : g[v]) {
      if (to == p || used[to]) {
        continue;
      }
      if (sz[to] * 2 > n) {
        return get_centroid(to, v);
      }
    }
    return v;
  };
  vector <int> subtree;
  function <void(int, int)> get_subtree = [&](int v, int p) {
    subtree.push_back(v);
    for (int to : g[v]) {
      if (to == p || used[to]) {
        continue;
      }
      get_subtree(to, v);
    }
  };
  int root = 1;
  do {
    subtree.clear();
    int centroid = get_centroid(root, par[root]);
    get_subtree(centroid, par[centroid]);
    if (query(subtree)) {
      root = centroid;
    } else {
      used[centroid] = true;
      int cur = centroid;
      while (par[cur] != -1) {
        sz[par[cur]] -= sz[centroid];
        cur = par[cur];
      }
    }
  } while ((int)subtree.size() > 1);
  return subtree.back();
}

Compilation message (stderr)

eastereggs.cpp: In function 'int findEgg(int, std::vector<std::pair<int, int> >)':
eastereggs.cpp:54:9: error: 'query' was not declared in this scope
   54 |     if (query(subtree)) {
      |         ^~~~~