走走停停的专栏

题目描述 Given a collection of numbers, return all possible permutations. For example, [1,2,3]have the following permutations: [1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2], and[3,2,1]. 题目大意 给定一个数组集合，返回所有可能的排列。...