Neetcode 150
Design Word Search Data Structure Medium Design a data structure that supports adding new words and searching for existing words. Implement the WordDictionary class: void addWord(word) Adds word to the data structure. bool search(word) 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. Copy Constraints: 1 <= word.length <= 20 word in addWord consists of lowercase English letters. word in search consist of '.' or lowercase English letters.
class TrieNode: def __init__(self): self.children = {} # a : TrieNode self.word = False class WordDictionary: def __init__(self): self.root = TrieNode() def addWord(self, word: str) -> None: cur = self.root for c in word: if c not in cur.children: cur.children[c] = TrieNode() cur = cur.children[c] cur.word = True def search(self, word: str) -> bool: def dfs(j, root): cur = root for i in range(j, len(word)): c = word[i] if c == ".": for child in cur.children.values(): if dfs(i + 1, child): return True return False else: if c not in cur.children: return False cur = cur.children[c] return cur.word return dfs(0, self.root)
