1582 articles
LC 19 Remove Nth Node From End of List is a classic one-pass interview problem at Amazon, Google, and Facebook that combines the dummy head sentinel with a two-pointer n-gap technique. Learn the optimal O(n) single-pass solution with Python and JavaScript, step-by-step dry run, and common interview traps.
LC 24 Swap Nodes in Pairs is a medium linked list interview problem at Microsoft and Bloomberg that tests precise multi-step pointer manipulation. Learn the iterative dummy-head approach and the recursive solution with Python and JavaScript, detailed visual dry run, and interview tips.
LC 328 Odd Even Linked List is a medium interview problem at Facebook, Amazon, and LinkedIn that tests your ability to maintain two separate pointer chains simultaneously. Learn the O(1) space two-chain pattern with Python and JavaScript, a visual dry run, and interview tips.
LC 61 Rotate List is a medium interview problem at Amazon and Microsoft that tests your ability to use circular linked list manipulation and modular arithmetic to rotate by k positions efficiently. Learn the optimal O(n) solution with Python and JavaScript, detailed dry run, and the critical k mod n insight.
LC 143 Reorder List is a composite interview problem at Facebook, Amazon, and Google that combines three core patterns: fast/slow midpoint finding, in-place second-half reversal, and interleaved merging. Master the O(1) space solution with Python and JavaScript, step-by-step visual trace, and interview approach.