LeetCode——500. Keyboard Row（模拟题）

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"]

Note:

1. You may use one character in the keyboard more than once.
2. You may assume the input string will only contain letters of alphabet.

题意：输出字符串组成都属于一排字母的字符串。

解题：

        确定首位的行值，随后逐位比较。

代码：

class Solution {
public:
    vector<string> findWords(vector<string>& words) {
        vector <string> res;
        string a[3]={"qwertyuiop","asdfghjkl","zxcvbnm"};
        int val[256];
        for(int i=0;i<3;i++){
            for(int j=0;j<a[i].length();j++){
                val[a[i][j]]=val[a[i][j]-32]=i+1;
            }
        }
        for(int i=0;i<words.size();i++)
        {
            bool flag=true;
            int fval=val[words[i][0]];
            if(fval>0){
                for(int j=1;j<words[i].length();j++){
                    if(val[words[i][j]]!=fval){
                        flag=false;
                        break;
                    }
                }
            }
            else flag=false;
            if(flag){
                res.push_back(words[i]);
            }
        }
        return res;
    }
};