js 一个数组各元素出现的次数,并输出,怎么写代码<script>var arr = [1, 5, 84, 4894, 44, 45, 454, 444, 515, 3, 4, 84, 4894, 44, 45, 454, 444, 515, 3, 4, 6, 6,2023-04-25JavaScript250