Hashing and Tries

Explain hashing, hash functions, and collision resolution strategies (chaining, open addressing).

Implement a hash table using chaining (array of linked lists).

Apply hash maps to solve frequency counting and lookup problems (e.g., Two Sum, Subarray Sum Equals K).

Apply hashing to find the longest consecutive subsequence in an array.

Implement a trie (prefix tree) with insert and search operations.

Implement word search and autocomplete features using a trie.

Solve problems involving finding all words from a dictionary on a 2D grid of characters using a trie and backtracking.