HashMap from Scratch

Implement a hashmap without using built-in hash-table libraries. The round centers on buckets, collision handling, resizing, hash-function tradeoffs, and clean get/put semantics. Requirements Design and implement a hashmap from scratch. At minimum, support: put(key, value) get(key) Do not use a built-in hash table / dictionary as the core storage. Discussion topics include: Bucket array layout. Linked-list or equivalent chaining for collision resolution. Hash-function choice and tradeoffs. Load factor and resizing / rehashing. Complexity under average and worst-case collision patterns. Notes The common baseline is an array of buckets, with each bucket storing a linked list of key-value pairs. Resizing must rehash existing entries into the new bucket array; simply copying buckets by index is incorrect. One candidate described the prompt as an upgraded version of a basic design-hashmap exercise, with more emphasis on discussion than just method implementation. Preparation Implement get, put, update-existing-key, and resize with separate chaining. Be ready to discuss open addressing versus chaining, and why deletion is trickier with probing. Test collisions deliberately by injecting a bad hash function.