从传递进来的字母序列中找到缺失的字母并返回它. 如果所有字母都在序列中,返回 undefined. function fearNotLetter(str) { var arr = str.split(""); var newArr = []; var start = str.charCodeAt(0); var end = str.charAt(str.length - 1).charCodeAt(0); for (var i = start; i < end+1; i++) {…

FCC-学习笔记  Missing letters 1>最近在学习和练习FCC的题目.这个真的比较的好,推荐给大家. 2>中文版的地址:https://www.freecodecamp.cn/;英文版的地址:https://www.freecodecamp.org 3>这次写关于一个JS的问题,名为Missing letters. 规则要求如下: 从传递进来的字母序列中找到缺失的字母并返回它. 如果所有字母都在序列中,返回 undefined 4>我写的代码实现如下: functi…

function fearNotLetter(str) { //return str; var arr = str.split(''); var temp = []; var start = str.charCodeAt(0); var end = str.charAt(str.length - 1).charCodeAt(0); for(var i = start; i < end + 1; i++){ var item = String.fromCharCode(i); if(arr[0]…

freecodecamp 中级算法地址戳这里 Sum All Numbers in a Range 我们会传递给你一个包含两个数字的数组.返回这两个数字和它们之间所有数字的和. function sumAll(arr) { arr.sort(function(a,b){ return a-b; }); var a=arr[0]; var sum=arr[0]; while( a<arr[1] ){ a++; sum+=a; } return sum; } sumAll([1, 4]); Diff…

Missing letters 1.要求 从传递进来的字母序列中找到缺失的字母并返回它. 如果所有字母都在序列中,返回 undefined. 2.思路 设定缺失变量miss 在for循环遍历字符串的各个字符时,判断后一个字符的UTF-16 代码单元值的数字与当前字符的UTF-16 代码单元值的数字的差值是否为1,否,则把对应缺失字母赋给miss,是则返回undefine 3.代码 function fearNotLetter(str) { var miss=''; for(var i=0;i<s…

题目描述 A pangram is a phrase that includes at least one occurrence of each of the 26 letters, ‘a’. . .‘z’. You’re probably familiar with this one: “The quick brown fox jumps over the lazy dog.”Your job is to recognize pangrams. For phrases that don’t c…

Description ZS the Coder loves to read the dictionary. He thinks that a word is nice if there exists a substring (contiguous segment of letters) of it of length 26 where each letter of English alphabet appears exactly once. In particular, if the stri…

A. Crazy Computer time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output ZS the Coder is coding on a crazy computer. If you don't type in a word for a c consecutive seconds, everything you typed…

B. Complete the Word time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output ZS the Coder loves to read the dictionary. He thinks that a word is nice if there exists a substring (contiguous segmen…

ZS the Coder loves to read the dictionary. He thinks that a word is nice if there exists asubstring (contiguous segment of letters) of it of length 26 where each letter of English alphabet appears exactly once. In particular, if the string has length…