水中的鱼

Share the pdf in case someone else interests in. Not for money, just for fun and my personal interests in this technology.  Download link：  ...

Implement an iterator to flatten a 2d vector. For example, Given 2d vector = [ [1,2], [3], [4,5,6] ] By calling  next  repeat...

Given a binary search tree, write a function  kthSmallest  to find the  k th smallest element in it. Note:  You may assume k is always v...

Implement a basic calculator to evaluate a simple expression string. The expression string contains only  non-negative  integers,  + ,  -...

Given a 2D binary matrix filled with 0's and 1's, find the largest square containing only 1's and return its area. For exampl...

There are a total of  n  courses you have to take, labeled from  0  to  n - 1 . Some courses may have prerequisites, for example to take ...

Given two strings S and T, determine if they are both one edit distance apart. [Thoughts] 这是个简化版。只要考虑几种可能， 如果s.length == t.length，只要看看不相同...