Find the maximum and minimum possible sums

You are given three arguments:

• arr = an array of numbers
• n = the size of the array
• k = number of reduced elements

The arguments are passed in the order: n, arr, k.

Your task is to write the function findMinMaxSums which computes the maximum and minimum possible sums of the elements in the array after having discarded exactly k elements. Return these numbers in an array: [max, min]. You should not use any sorting library functions.

Example 1

Input:

• n = 5
• arr = 1 2 3 4 5
• k = 1

Logic:

• Remove the lowest number.
• The maximum amount is: 2 + 3 + 4 + 5 = 14.
• Remove the highest number.
• The minimum amount is: 1 + 2 + 3 + 4 = 10.
• Output: 14 10

Example 2

Input:

• n = 3
• arr = 5 6 7
• k = 2

Logic:

• Remove the two lowest numbers: 7
• Remove the two highest numbers: 5
• Output: 7 5