def countInversions(arr): def merge_sort_and_count(arr): if len(arr) <= 1: return arr, 0 mid = len(arr) // 2 left, left_inversions = merge_sort_and_count(arr[:mid]) right, right_inversions = merge_sort_and_count(arr[mid:]) merged, split_inversions = merge_and_count(left, ...
In an array, , the elements at indices and (where ) form an inversion if . In other words, inverted elements and are considered to be "out of order". To correct an inversion, we can swap adjacent elements. For example, consider the dataset . It has two inversions: and . To sort th...