Function dist

Graph Theory/Virtual Tree.cpp:32–35

  return u;
}
int dist(int u, int v) {
  int lc = lca(u, v);
  return dep[u] + dep[v] - 2 * dep[lc];
}
int isanc(int u, int v) {
  return (st[u] <= st[v]) && (en[v] <= en[u]);
}