How to implement this pseudo code to Java, for a file that contains 100k elements

This is the first part

This is the second part

In Java please

Sort-and-CountInv Input: array A of n distinct integers. Output: sorted array B with the same integers, and the number of inversions of A. if n = 0 or n= 1 then // base cases return (A,0) else (C, leftInv) := Sort-and-CountInv(first half of A) (D, rightInv) := Sort-and-CountInv(second half of A) (B, split Inv) := Merge-and-CountSplitInv(C, D) return (B, leftInv + rightInv + split Inv) Merge-and-CountSplitInv Input: sorted arrays C and D (length n/2 each). Output: sorted array B (length n) and the number of split inversions. Simplifying assumption: n is even. i:=1, j :=1, split Inv := 0 for k:=1 to n do if C[i]