Turn beginWord into endWord by changing one letter at a time, where every intermediate word (and endWord) must be in wordList. Return the number of words in the shortest such sequence, counting beginWord, or 0 if none exists.
The highlighted line runs next. The pill shows the live values in the running call.
The data structures the code is building
Edges join words one letter apart; columns = distance from beginWord
n = words in wordList, m = word length. The highlighted row is the solution being traced.
Keyboard: ← → step, Space play or pause. Words up to 5 letters, at most 12 in wordList, separated by commas. Words that beginWord can never reach are drawn in the last column.