Medium
Design a data structure with addWord(word) and search(word). In search, a . can match any single letter. search returns whether any added word matches.
Input: operations = ["WordDictionary","addWord","addWord","addWord","search","search","search","search"], values = [[],["bad"],["dad"],["mad"],["pad"],["bad"],[".ad"],["b.."]] Output: [null,null,null,null,false,true,true,true]