摘要：
Given a non-negative number represented as an array of digits, plus one to the number. The digits are stored such that the most significant digit is a 阅读全文
摘要：
Given a linked list, determine if it has a cycle in it. Follow up: Can you solve it without using extra space? Subscribe to see which companies asked 阅读全文
摘要：
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 f 阅读全文