Question
Return the Levenshtein edit distance between two strings a and b: the minimum number of single-character insertions, deletions, or substitutions needed to turn a into b. For example, turning "kitten" into "sitting" takes 3 edits. Either string may be empty. Strings can be up to a few thousand characters, so use O(len(a)*len(b)) time and try to keep memory to O(min(len(a), len(b))).
edit_distance(a: str, b: str) → int["kitten","sitting"]out3State your approach and its time/space complexity out loud before you optimize. Handle the edge cases (empty input, duplicates, overflow), and say why you chose this over the brute force. Green tests are the floor, not the grade.
Vibe coding: describe the solution in plain language (or narrate it) and the coach grades your approach. Generating runnable code from your description is coming next.