封装两个函数

randomClass

传入两个参数 total（总人数）和 num（班级数）返回分班结果

randomClass(67, 3);
//第 1 组名单为：[5,6,12,14,22,24,31,32,34,35,36,37,40,42,44,45,47,48,55,58,60,62,65]班级人数23
//第 2 组名单为：[1,2,7,10,11,15,16,18,19,25,28,30,32,35,37,41,45,46,48,54,61,66]班级人数 22
//第 3 组名单为：[3,4,6,11,13,17,19,20,23,26,27,32,37,38,39,46,49,50,53,57,59,64]班级人数 22

addBigNum

实现两个 20 位长度大数相加

let num1 = 100000000000000000000; //21位
let num2 = 200000000000000000000; //21位
addBigNum(num1, num2);