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Design Add And Search Words

Detailed guide and Python implementation for the 'Design Add And Search Words' problem.

Problem Statement

Easy

Design a data structure that supports adding new words and finding if a string matches any previously added string.

Implement the WordDictionary class:

- WordDictionary() Initializes the object.

- addWord(word: str) Adds word to the data structure, it can be matched later.

- search(word: str) -> bool Returns True if there is any string in the data structure that matches word or False otherwise. word may contain dots '.' where dots can be matched with any letter.

Input is a list of operations and arguments. Implement a function wordDictionary(operations: list, arguments: list) -> list that returns a list of results (None for constructor/addWord, bool for search).

Constraints
  • 1 <= len(word) <= 25
  • word in addWord consists of lowercase English letters
  • word in search consists of '.' or lowercase English letters
  • At most 10^4 calls will be made to addWord and search

Examples

Example 1
Input
operations = ["WordDictionary", "addWord", "addWord", "addWord", "search", "search", "search", "search"], arguments = [[], ["bad"], ["dad"], ["mad"], ["pad"], ["bad"], [".ad"], ["b.."]]
Output
[None, None, None, None, False, True, True, True]
Explanation

Initialize. Add "bad", "dad", "mad". search("pad") -> False. search("bad") -> True. search(".ad") -> True. search("b..") -> True.

Need a Hint?
Consider using Trie-specific data structures like sets or heaps.
Edge Cases to Watch
  • Empty input structures
  • Single element inputs
  • Large numerical bounds

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