题解 | #数组排序#

let resDOM = (arr) => {
	let str = ''
	arr.forEach(e => str += `<li>${e.name}</li>`)
    ul.innerHTML = str
}
upbtn.onclick = () => {
	cups.sort((a,b) => a.sales - b.sales)
	resDOM(cups)
}
downbtn.onclick = () => {
	cups.sort((a,b) => b.sales - a.sales)
    resDOM(cups)
}