Given a linked list, reverse the nodes of a linked list k at a time and return its modified list.
整理一些我自己用過的 LaTex 數學符號指令，下次就不用再像無投蒼蠅般亂找了 XD
Validate if a given string can be interpreted as a decimal number.
You’re given strings J representing the types of stones that are jewels, and S representing the stones you have. Each character in S is a type of stone you have. You want to know how many of the stones you have are also jewels.
Given a non-empty array of digits representing a non-negative integer, plus one to the integer.
Given two non-negative integers
num2 represented as strings, return the product of
num2, also represented as a string.
Given an absolute path for a file (Unix-style), simplify it.
In a UNIX-style file system, a period (‘.’) refers to the current directory, so it can be ignored in a simplified path.
Implement a trie with
Given an array, rotate the array to the right by k steps, where k is non-negative.