LeetCode 500. Keyboard Row

Given a List of words, return the words that can be typed using letters of alphabet on only one row's of American keyboard like the image below.

Example 1:

Input: ["Hello", "Alaska", "Dad", "Peace"]Output: ["Alaska", "Dad"]

如上所示，要求找出由键盘某一行中字母组合而成的单词。

解决方法：将各行字母分别存入Hash Table中，然后逐个判断数组中字符串即可。具体实现如下：

class Solution {public:    vector<string> findWords(vector<string>& words) {    vector<string> result;    map<char,int>hash;    hash['Q']=hash['q']=1;    hash['W']=hash['w']=1;    hash['E']=hash['e']=1;    hash['R']=hash['r']=1;    hash['T']=hash['t']=1;    hash['Y']=hash['y']=1;    hash['U']=hash['u']=1;    hash['I']=hash['i']=1;    hash['O']=hash['o']=1;    hash['P']=hash['p']=1;    hash['A']=hash['a']=2;    hash['S']=hash['s']=2;    hash['D']=hash['d']=2;    hash['F']=hash['f']=2;    hash['G']=hash['g']=2;    hash['H']=hash['h']=2;    hash['J']=hash['j']=2;    hash['K']=hash['k']=2;    hash['L']=hash['l']=2;    hash['Z']=hash['z']=3;    hash['X']=hash['x']=3;    hash['C']=hash['c']=3;    hash['V']=hash['v']=3;    hash['B']=hash['b']=3;    hash['N']=hash['n']=3;    hash['M']=hash['m']=3;    for(int i =0;i<words.size();++i){    string s = words[i];    int row = hash[s[0]];    bool inOneRow = true;    for(int j =0;j<s.length();++j){    char c=s[j];    if(hash[c] != row){    inOneRow = false;    break;    }    }    if(inOneRow)    result.push_back(s);    }    return result;    }};