//set用法
const arr = [1, 2, 3, 4, 5, 5, 4, 3, 2, 1];
const set = new Set(arr);
console.log(...set);
set.add(8);
console.log(...set,"添加后");
set.delete(1);
console.log(...set,"删除后");
// set.has(10);
// console.log(...set,"has后");
set.clear();
console.log(...set,"清除后的");
var arr1 =[1,2,3,4,5,2,3,4];
const set1 = new Set(arr1);
console.log(...set1);
const brr =Array.from(set1);
console.log(brr,'brr');
var cc=[1,2,3,4,5];
var dd=[0,9,8,7,6];
var ee=cc.concat(dd);
console.log(ee,"ee");
ee.sort();
console.log(ee);
ee.reverse();
console.log(ee,"ee")