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 > Divisible by Digit Count > Editorial

Divisible by Digit Count — Solution & Editorial

Back to the Problem

Group by digit length: within one length L the qualifying numbers are the multiples of L in that length's range — count them with floor division. Sum over lengths with a prefix difference.

Complexity: O(number of digit lengths)