百草园

摘要：Bulls and CowsYou are playing the followingBulls and Cowsgame with your friend: You write a 4-digit secret number and ask your friend to guess it, eac... 阅读全文

摘要：Serialize and Deserialize Binary TreeSerialization is the process of converting a data structure or object into a sequence of bits so that it can be s... 阅读全文

摘要：Find Median from Data StreamMedian is the middle value in an ordered integer list. If the size of the list is even, there is no middle value. So the m... 阅读全文

摘要：Convert Sorted List to Binary Search TreeGiven a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST.... 阅读全文

摘要：Nim GameYou are playing the following Nim Game with your friend: There is a heap of stones on the table, each time one of you take turns to remove 1 t... 阅读全文

摘要：Word PatternGiven apatternand a stringstr, find ifstrfollows the same pattern.Examples:pattern ="abba", str ="dog cat cat dog"should return true.patte... 阅读全文

摘要：Unique Word AbbreviationAn abbreviation of a word follows the form . Below are some examples of word abbreviations:a) it --> it ... 阅读全文