Hiring process8 levels
  1. 1 IQ Test
  2. 2 Additional Online Test (If Required)
  3. 3 Office Interview with Hiring Manager
  4. 4 Unpaid Test Task (Motivation Check)
  5. 5 Paid Test Task and Follow-Up Interview
  6. 6 Iterative Paid Test Tasks
  7. 7 Office Verification
  8. 8 Final Interview with the Founder

Problems > Distances at Scale > Editorial

Distances at Scale — Solution & Editorial

Back to the Problem

dist(a, b) = depth(a) + depth(b) − 2·depth(LCA). Binary-lifting LCA answers each query in O(log N); per-query BFS is O(NQ) and dies.

Complexity: O((N + Q) log N)