Sum the largest five numbers
We need only 5 maximum elements, for that we don't need to sort whole array. We can use alternative approach

Approach 1: Use 5 local variables and keep track of minimum element in it.

Approach 2: Use Min-heap and insert first 5 elements of array in min-heap, then iterate on array from index = 5, if heap-root is smaller than number in array then extract that number from min-heap, and insert new.