js使用数组重组方法返回课程名称及返回课程数量

Question

//返回每个系列名称，及每个系列一共有多少个课（lesson的总数）;问题出现的环境背景及自己尝试过哪些方法相关代码constSeries=[{name:'Web',courses:[{name:'HTML',lessons:[{name:'HTMLLesson1'},{name:'HTMLLesson2'},{name:'HTMLLesson3'}]},{name:'CSS',lessons:[{name:'CSSLesson1'},{name:'CSSLesson2'},{name:'CSSLesson3'},{name:'CSSLesson4'}]},{name:'JavaScript',lessons:[{name:'JavaScriptLesson1'},{name:'JavaScriptLesson2'}]}]},{name:'PHP',courses:[{name:'Linux',lessons:[{name:'LinuxLesson1'},{name:'LinuxLesson2'}]},{name:'MySQL',lessons:[{name:'MySQLLesson1'},{name:'MySQLLesson2'},{name:'MySQLLesson3'},{name:'MySQLLesson4'}]},{name:'Nginx',lessons:[{name:'NginxLesson1'},{name:'NginxLesson2'},{name:'NginxLesson3'},{name:'NginxLesson4'}]}]}]functionoutput3(Series){//...}output3(Series)题目来源及自己的思路aitschool求解答和思路

Answer 1

functionoutput(arr){
returnarr.map(item=>{
item.lessonCount=item.courses.reduce((total,cur)=>{
total+=cur.lessons.length
returntotal
},0)
deleteitem.courses
returnitem
})
}