摘要： 题目：Count Complete Tree NodesGiven acompletebinary tree, count the number of nodes.Definition of a complete binary tree fromWikipedia:In a complete bin... 阅读全文

摘要： 题目：Basic CalculatorImplement a basic calculator to evaluate a simple expression string.The expression string may contain open(and closing parentheses)... 阅读全文

摘要： 题目：Implement Stack using QueuesImplement the following operations of a stack using queues.push(x) -- Push element x onto stack.pop() -- Removes the el... 阅读全文