James Pan

原题网址：https://leetcode.com/problems/reverse-integer/ Reverse digits of an integer. Example1: x = 123, return 321 Example2: x = -123, return -321 click to show spoilers. Have you thought

原题网址：https://leetcode.com/problems/palindrome-number/ Determine whether an integer is a palindrome. Do this without extra space. click to show spoilers. Some hints: Could negative integers

原题网址：https://leetcode.com/problems/permutation-sequence/ The set [1,2,3,…,n] contains a total of n! unique permutations. By listing and labeling all of the permutations in order, We get the