500. Keyboard Row

最新推荐文章于 2024-11-23 18:25:02 发布

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本文介绍了一种算法，用于从给定的单词列表中筛选出仅使用美式键盘单行字母即可完成输入的单词。通过构建键盘字母映射表，并检查每个单词中的字母是否位于同一行来实现。

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.

American keyboard

Example 1:

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

Note:

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

思路：就是判断是不是在一行内

代码1：

class Solution {
public:
    vector<string> findWords(vector<string>& words) {
        if(words.size()==0){return words;}
        string a[3]={"qwertyuiop","asdfghjkl","zxcvbnm"};
        map<char,int> keyboard;
        int i=0;
        for(string st:a){
            for(char ch:st){
                keyboard[ch]=i;
            }
            i++;
        }
        vector<string> result;
        for(string ss:words){
            bool flag=true;
            char head=ss[0];
            if(head<'a'){head=ss[0]+32;}
            for(char ch:ss){
                if(ch<'a'){ch=ch+32;}
                if(keyboard[head]!=keyboard[ch]){
                    flag=false;
                    break;
                }
            }
            if(flag){result.push_back(ss);}
        }
        return result;
    }
};

代码2：

class Solution {
public:
    vector<string> findWords(vector<string>& words) {
        vector<string> keyb,res;
        map<char,int> m;
        keyb.push_back("qwertyuio");
        keyb.push_back("asdfghjkl");
        keyb.push_back("zxcvbnm");
        for(int i=0;i<3;i++){
            for(char ch:keyb[i]){m[ch]=i;}
        }
        for(string word:words){
            set<int> temp;
            for(char ch:word){
                if(isupper(ch)){ch=tolower(ch);}
                temp.insert(m[ch]);
            }
            if(temp.size()==1){res.push_back(word);}
    }
        return res;
    }
};

isupper/islower/toupper/tolower->头文件<cctype>