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 > Walks of Astronomical Length > Editorial

Walks of Astronomical Length — Solution & Editorial

Back to the Problem

The adjacency matrix's K-th power counts walks: entry (1, N) of AK. Binary exponentiation of the matrix does it in O(N³ log K).

Complexity: O(N3 log K)