摘要：
You are given two string arrays username and website and an integer array timestamp. All the given arrays are of the same length and the tuple [userna 阅读全文
摘要：
Let's define a function countUniqueChars(s) that returns the number of unique characters on s. For example, calling countUniqueChars(s) if s = "LEETCO 阅读全文
摘要：
You are given an integer array nums. The range of a subarray of nums is the difference between the largest and smallest element in the subarray. Retur 阅读全文