摘要：
We are given an array A of N lowercase letter strings, all of the same length. Now, we may choose any set of deletion indices, and for each string, we 阅读全文
摘要：
Create a timebased key-value store class TimeMap, that supports two operations. 1. set(string key, string value, int timestamp) Stores the key and val 阅读全文
摘要：
In a country popular for train travel, you have planned some train travelling one year in advance. The days of the year that you will travel is given 阅读全文