摘要：
Given a collection of distinct integers, return all possible permutations.Example:Input: [1,2,3]Output:[ [1,2,3], [1,3,2], [2,1,3],... 阅读全文
摘要：
Given two strings s1 and s2, write a function to return true if s2 contains the permutation of s1. In other words, one of the first st... 阅读全文