500.md

500. Keyboard Row

Description

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.

Solution

Solution 1

/**
 * @param {string[]} words
 * @return {string[]}
 */
var findWords = function(words) {
    "use strict";
    let rows = ["qwertyuiop", "asdfghjkl", "zxcvbnm"];
    return words.filter((word) => {
        word = word.toLowerCase();
        for (let i = 0; i < rows.length; i++) {
            for (let j = 0; j < word.length; j++) {
                if (!rows[i].includes(word[j])) {
                    if (i === rows.length-1) {
                        return false;
                    }
                    break;
                } else {
                    if (j === word.length-1) {
                        return true;
                    }
                }
            }
        }
    });
};

Solution 2

/**
 * Solved with regular expression
 * @param {string[]} words
 * @return {string[]}
 */
var findWords = function(words) {
    "use strict";
    return words.filter((word) => {
        word = word.toLowerCase();
        return word.replace(/[qwertyuiop]/g, "").length === 0 ||
            word.replace(/[asdfghjkl]/g, "").length === 0 ||
            word.replace(/[zxcvbnm]/g, "").length === 0;
    });
};