String

LeetCode note for Delete Operation for Two Strings, rebuilt from the original learning note

LeetCode note for Distinct Subsequences, rebuilt from the original learning note

LeetCode note for Interleaving String, rebuilt from the original learning note

LeetCode note for Edit Distance, rebuilt from the original learning note

LeetCode 316 note: a monotonic stack with last positions; pop a larger top that appears again later, and skip letters already on the stack

LeetCode 726 note: tokenize into elements, numbers, and parentheses; handle parentheses with a stack, with a default multiplier of 1

LeetCode note for Longest Palindromic Subsequence, rebuilt from the original learning note

LeetCode note for Longest Common Subsequence, rebuilt from the original learning note

LeetCode 488 note: with at most 16 balls on the board and 5 in hand, memoize DFS on the whole (board, hand) state, inserting only before a same-colored ball or between two equal balls

LeetCode 1147 note: build strings inward from both ends and cut a pair as soon as they match; cutting early is best, and any leftover middle counts as one chunk

LeetCode 1745 note: build is_pal[i][j] with interval DP, then try both cut points; three palindromic parts means true, O(n^2)

LeetCode 3713 note: fix the start and extend right; “every character has the same count” means “highest count × kinds = length”, an O(1) check per step