Software Engineer

Given an array ‘arr’ consisting of ‘N’ integer elements. You have to remove ‘K’ elements from the beginning or end of the array. Return the maximum possible sum of the remaining array elements.

Note: you can remove elements from both beginning and end, but a total of ‘K’ elements must be removed.

Example :

If N = 7 and K = 3, and the input array is:
{1, 2, 3, 4, 5, 6, 7}

After removing the first three elements, the resulting array now becomes {4, 5, 6, 7} and the sum of the remaining array is equal to 22.

Removing any other combination of three elements will always result in the remaining array sum less than 22.

Given a N * N matrix and the task is to check matrix is idempotent matrix or not.

See the sample input.

Idempotent matrix M follows the following property :

M*M = M

You are given an array Arr consisting of n integers, you need to find a valid triplet as explained below.

An array is said to have a valid triplet {arr[i], arr[j], arr[k]} if there exists three indices i, j and k such that i != j, j != k and i != j and arr[i] + arr[j] = arr[k] or arr[i] + arr[k] = arr[j] or arr[k] + arr[j] = arr[i].

For Example:

Arr = 10, 5, 5, 6, 2, 
In this array, the triplet {10, 5, 5} is valid triplet because, 5 + 5 = 10.

Note:

The elements in the array need not be distinct.