Tiger's leetcode solution

  Given two   sparse matrices   A   and   B , return the result of   AB . You may assume that  A 's column number is equal to  B 's ...

Design a Phone Directory which supports the following operations:   get : Provide a number which is not assigned to anyone. check : Check if...

  Given two strings  s   and   t , you want to transform string  s   into string  t   using the following operation any number of times: Cho...

  Given the root of a binary tree, find the largest subtree, which is also a Binary Search Tree (BST), where the largest means subtree has t...

  Consider the string   s   to be the infinite wraparound string of "abcdefghijklmnopqrstuvwxyz", so   s   will look like this: ...

 

  Design a logger system that receive stream of messages along with its timestamps, each message should be printed if and only if it is   no...