摘要： Write a function that takes a string as input and returns the string reversed. Example:Given s = "hello", return "olleh". 链接：https://leetcode.com/prob 阅读全文

摘要： 题目 Given an integer (signed 32 bits), write a function to check whether it is a power of 4. Example:Given num = 16, return true. Given num = 5, return 阅读全文

摘要： 题目： Given a nested list of integers, return the sum of all integers in the list weighted by their depth. Each element is either an integer, or a list 阅读全文