Fullstack Developer

You are given a string 'str' of lowercase alphabets and an integer 'k' .

Your task is to return the count all the possible substrings that have exactly 'k' distinct characters.

For example:

'str' = abcad and 'k' = 2. 

We can see that the substrings {ab, bc, ca, ad} are the only substrings with 2 distinct characters. 

Therefore, the answer will be 4.    

You are given a matrix of ‘M’ rows and ‘N’ columns. The cells of the matrix contain either a coin or are empty.

You are allowed to visit every boundary cell that has a coin in it and collects that coin apart from that, you are allowed to collect the coin in one of the four adjacent cells. Find the maximum number of coins that you can collect from the matrix.

For Example :

If Matrix of size 3 * 5 is: 
0 1 1 0 0
0 1 0 1 0
1 0 0 0 0


Then, out of the five coins in the matrix, you can collect a maximum of four coins. This is because the coin at (0, 1) lies on the boundary and after collecting the coin one can also collect the coin at (1, 1) as it lies in the adjacent cell. We can also collect the coin at (2, 0). But we cannot collect the coin at (1, 3), as this coin doesn’t lie on the boundary and it cannot be reached from one of the boundary coins.

Alex has a computer with ‘K’ memory spaces. He has a list of ‘N’ different document downloads that he would like to do, each of which consumes some unique memory usage. He also has ‘M’ computer games, each of which consumes some unique memory usage. His computer can allow at most one download and at most one game to run simultaneously, provided that the sum of memory usages doesn’t exceed ‘K’. Alex wants to play at most one game and complete at most one download so that the total memory usage is maximum.

Given a list ‘download’ and a list ‘game’, help Alex find out the number of pairs of downloads and games such that the sum of memory usages is maximum. It can also be possible that Alex only plays a game or performs a download at a time.

What is segmentation?
What is paging?
All the concepts of paging.

What is size of session cookie?
Difference between TCP and UDP.
Explain OSI model.
Different layers of OSI model.