小编RSP*_*RSP的帖子

我有一个如下所示的数组：

let totalArr = ["First","Second","Third","Fourth","First","Second", "Second"]

我所需的输出是：

let grouper = [["First","First"],["Second", "Second", "Second"],["Third"],  ["Fourth"]]

有人可以给出最佳迭代吗？