Klarna Coding Interview Questions
25 Klarna coding interview problems with full optimal solutions — 11 easy, 11 medium, 3 hard. Every problem ships with multiple approaches (brute-force first, then the optimal), complexity tables for each, company-specific tips on what an Klarna interviewer values, and a FAQ section.
Showing 11 problems of 25
- #12mediumfoundational
12. Add Two Numbers
Add two non-negative integers represented as reversed linked lists, digit per node.
- #13mediumfoundational
13. Longest Substring Without Repeating Characters
Find the length of the longest substring with all distinct characters.
- #14mediumfoundational
14. Container With Most Water
Find two vertical lines that, together with the x-axis, form a container holding the most water.
- #15mediumfoundational
15. 3Sum
Find all unique triplets in an array that sum to zero.
- #16mediumfoundational
16. Group Anagrams
Group strings that are anagrams of each other.
- #17mediumfoundational
17. Maximum Subarray
Find the contiguous subarray with the largest sum.
- #18mediumfoundational
18. Spiral Matrix
Return all elements of a matrix traversed in spiral order.
- #19mediumfoundational
19. Jump Game
Decide if you can reach the last index starting from index 0 using each cell's max jump length.
- #20mediumfoundational
20. Merge Intervals
Merge all overlapping intervals into a minimal disjoint set.
- #21mediumfoundational
21. Unique Paths
Count the number of unique paths from the top-left to bottom-right of an m x n grid, moving only right or down.
- #22mediumfoundational
22. Coin Change
Find the fewest coins needed to make a target amount, or -1 if impossible.