Intern

You have been given an unsorted array ‘ARR’.

Your task is to sort the array in such a way that the array looks like a wave array.

Example:

If the given sequence ‘ARR’ has ‘N’ elements then the sorted wave array looks like - 
‘ARR[0] >= ARR[1]’ and ‘ARR[1] <= ARR[2]’
‘ARR[2] >= ARR[3]’ and ‘ARR[3] <= ARR[4]’
‘ARR[4] >= ARR[5]’ and ‘ARR[5] <= ARR[6]’  And so on.

Note:

1. ‘ARR[0]’ must be greater than or equal to ‘ARR[1]’.

2. There can be multiple arrays that look like a wave array but you have to return only one.

3. We have an internal function that will check your solution and return 'True' in case your array is one of the solutions otherwise return 'False'.

Explanation

The given array ‘ ARR = { 4, 3, 5, 2, 3, 1, 2 } ’
The below figure is a visual representation of the given ‘ARR’ and you can see we can express ‘ARR’ in a waveform array because 
4>3 and 3<5 
5>2 and 2<3
3>1 and 1<2
And it follows the condition of wave array.

Follow up:

Try to solve this problem in linear time complexity.

The Ultimate Ninja Ankush is playing a game where he has a grid of ‘N’ * ‘M’ size and each block of the grid has some coins. The Ultimate Ninja ankush is carrying a knapsack that can fit only ‘K’ coins, and since he is very greedy, he wants to know the number of paths where he can collect exactly ‘K’ coins. He is initially at the top-left and wants to reach bottom-right

More formally, return the number of paths whose total sum of coins is equal to ‘K’ from 0,0 to ‘N - 1’, ‘M - 1’.

Note:

Since the answer can be very large print the answer modulo 10 ^ 9 + 7.

For example

Given:
‘N’ = 3, ‘M’ = 3
‘Grid[][]’ = [[5, 2, 5],
              [3, 3, 1],
              [3, 5, 1]]
‘K’ = 14.
The answer will be 1, since There is only 1 path that is from (0,0) to (0,1) to (0,2) to (1,2) to (2,2) this is because 5 + 2 + 5 + 1 + 1 = 14

Spark related question: how we can store 100 GB files in spark?

How do I solve unknown problems, and what is my approach?

Normalization in DBMS. (Learn)
 

Company basic details like where its headquarters is located.
When was it founded?