leetcode 676. Implement Magic Dictionary 实现查询字典

悠悠 2022-06-03 08:22 81阅读 0赞

Implement a magic directory with buildDict, and search methods.

For the method buildDict, you’ll be given a list of non-repetitive words to build a dictionary.

For the method search, you’ll be given a word, and judge whether if you modify exactly one character into another character in this word, the modified word is in the dictionary you just built.

Example 1:  
Input: buildDict(\[“hello”, “leetcode”\]), Output: Null  
Input: search(“hello”), Output: False  
Input: search(“hhllo”), Output: True  
Input: search(“hell”), Output: False  
Input: search(“leetcoded”), Output: False  
Note:  
You may assume that all the inputs are consist of lowercase letters a-z.  
For contest purpose, the test data is rather small by now. You could think about highly efficient algorithm after the contest.  
Please remember to RESET your class variables declared in class MagicDictionary, as static/class variables are persisted across multiple test cases. Please see here for more details.

本题很简单，直接暴力查询即可，不过本题题意应该是使用前缀树来加速查询，但是这里就这么做了

代码如下：

#include <iostream>
    #include <vector>
    #include <map>
    #include <set>
    #include <queue>
    #include <stack>
    #include <string>
    #include <climits>
    #include <algorithm>
    #include <sstream>
    #include <functional>
    #include <bitset>
    #include <numeric>
    #include <cmath>
    #include <regex>
    
    using namespace std;
    
    class MagicDictionary 
    {
    public:
    
        set<string> myset;
        /** Initialize your data structure here. */
        MagicDictionary() 
        {
    
        }
    
        /** Build a dictionary through a list of words */
        void buildDict(vector<string> dict)
        {
            for (string s : dict)
                myset.insert(s);
        }
    
        /** Returns if there is any word in the trie that equals to the given word after modifying exactly one character */
        bool search(string word) 
        {
            for (int i = 0; i < word.length(); i++)
            {
                char t = word[i];
                for (char c = 'a'; c <= 'z'; c++)
                {
                    if (c == t)
                        continue;
                    word[i] = c;
                    if (myset.find(word)!=myset.end())
                        return true;
                }
                word[i]= t;
            }
            return false;
        }
    };
    
    /**
    * Your MagicDictionary object will be instantiated and called as such:
    * MagicDictionary obj = new MagicDictionary();
    * obj.buildDict(dict);
    * bool param_2 = obj.search(word);
    */