Palindrome

Subtitle / Summary 131. Palindrome Partitioning is not hard because of recursion alone. The real challenge is separating two concerns clearly: where the next cut starts, and whether the current substring is a valid palindrome. Reading time: 15-18 min Tags: Hot100, backtracking, string, palindrome, DP SEO keywords: Palindrome Partitioning, backtracking, palindrome DP, string partition, LeetCode 131 Meta description: Learn LeetCode 131 by building the solution from scratch, using suffix-based DFS plus a precomputed palindrome table. A — Algorithm Problem Restatement Given a string s, partition it so that every substring in the partition is a palindrome. Return all possible palindrome partitionings of s. ...

Subtitle / Summary The core of palindrome validation is symmetric comparison, but a singly linked list cannot move backward. The most stable engineering template is: find middle -> reverse second half in-place -> compare -> reverse back to restore. Reading time: 10-14 min Tags: Hot100, linked list, fast slow pointers, in-place reverse SEO keywords: Palindrome Linked List, fast slow pointers, reverse second half, O(1) space, LeetCode 234 Meta description: O(n)/O(1) palindrome check for singly linked list with middle detection, second-half reversal, comparison, and full structure restoration. A - Algorithm (Problem and Algorithm) Problem Restatement Given the head of a singly linked list head, return true if it is a palindrome; otherwise return false. ...