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Solution: Design Add and Search Words Data Structure

Explore how to design a WordDictionary using a trie data structure to support adding words, searching with exact and wildcard matches, and retrieving all stored words. Understand the algorithm's time and space complexities and its practical implementation for efficient string management.

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Statement

Design a data structure called WordDictionary that supports the following functionalities:

  • Constructor: This function will initialize the object.

  • Add Word(word): This function will store the provided word in the data structure.

  • Search Word(word): This function will return TRUE if any string in the WordDictionary object matches the query word. Otherwise, it will return FALSE. If the query word contains dots, ., each dot is free to match any letter of the alphabet.

    For example, the dot in the string “.ad” can have 2626 possible search results like “aad”, “bad”, “cad”, and so on.

  • Get Words(): This function will return all the words in the WordDictionary class.

Constraints:

  • 1≤1 \leq word.length ≤25\leq 25

  • Words passed to Add Word() consist of lowercase English letters.

  • Words passed to Search Word() consist of . or lowercase English letters.

  • There will be, at most, three dots in a word passed to Search Word().

  • At most, 10210^2 calls will be made to Add Word() , Get Words() and Search Word(). ... ...