Practice · 3 of 3

Digit Harmony

CHALLENGE

Difficulty: advanced+25 XP

**Problem.** Line 1: N (up to 1e18, given as a string). Line 2: k. Print how many x in [1, N] have digitSum(x) divisible by k. **Constraints:** 1 <= N <= 1e18; 2 <= k <= 100. **R versus W.** The graded wrong solution enumerates every number.

Press Submit to check your solution.

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