摘要：
1 """ 2 Design and implement a data structure for Least Recently Used (LRU) cache. It should support the following operations: get and put. 3 get(key) 阅读全文
摘要：
1 """ 2 Implement a basic calculator to evaluate a simple expression string. 3 The expression string contains only non-negative integers, +, -, *, / o 阅读全文
摘要：
1 """ 2 Given a non-empty array of digits representing a non-negative integer, plus one to the integer. 3 The digits are stored such that the most sig 阅读全文