58. 最后一个单词的长度

官方的

var lengthOfLastWord = function(s) {
    let index = s.length - 1;
    while (s[index] === ' ') {
        index--;
    }
    let wordLength = 0;
    while (index >= 0 && s[index] !== ' ') {
        wordLength++;
        index--;
    }
    return wordLength;
};

我的

/**
 * @param {string} s
 * @return {number}
 */
var lengthOfLastWord = function(s) {
let arr  =s.split(' ');
element= ''
arr = arr.filter(item => item != element)
return arr[arr.length-1].length
};

split

split()  通过搜索模式将字符串分割成一个有序的子串列表，将这些子串放入一个数组，并返回该数组。

const str = 'The quick brown fox jumps over the lazy dog.';

const words = str.split(' ');
console.log(words[3]);
// Expected output: "fox"

const chars = str.split('');
console.log(chars[8]);
// Expected output: "k"

const strCopy = str.split();
console.log(strCopy);
// Expected output: Array ["The quick brown fox jumps over the lazy dog."]

筛选数组中不想要的元素

element= ''
arr = arr.filter(item => item != element)