GoogleQuestions

Google Question:

Round 1:

https://leetcode.com/problems/single-number-ii
Round 2:

https://leetcode.com/problems/decode-string
Round 3:

Given a tree representation of a html parsed output, wherein every block is a node in the tree, find if two html docs contain the same text.

Explanation
Round 4:

Given a 2D matrix M X N, support two operations:
Query(row1, col1, row2, col2) such that I get the sum of all numbers in the rectangle ((row1, col1), (row1, col2), (row2, col1), (row2, col2)) and
Update(row, col) to a new number

And query is a very frequent operation and update is a rare operation, so query should be really fast, but update can be slower.

Follow up: How would you solve this in a distributed fashion

Round 5:

https://leetcode.com/problems/toeplitz-matrix
Follow-up: assume that the whole matrix cannot be fit in memory and should be read from a file, assume that a few rows and all columns can be read in, how to verify?