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 > Digits on the Pages > Editorial

Digits on the Pages — Solution & Editorial

Back to the Problem

Group by digit-length: the d-digit numbers span [10^(d−1), 10^d−1]; each contributes d digits. Sum the clipped blocks.

Complexity: O(log N)