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BJP3 Exercise 15.14: printInversions

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Author: Marty Stepp (on 2013/04/01)

Write a method printInversions that lists all inversions in a list of integers. An inversion is defined as a pair of numbers where the first appears before the second in the list, but the first is greater than the second. Thus, for a sorted list such as [1, 2, 3, 4] there are no inversions at all, and printInversions would produce no output. Suppose that a variable called list stores a list in reverse order, as in [4, 3, 2, 1]. Then the call: list.printInversions(); would print many inversions: 

(4, 3)
(4, 2)
(4, 1)
(3, 2)
(3, 1)
(2, 1)

You must reproduce this format exactly and output your inversions in the same order. Notice that any given number (e.g., 4 in the list above) can produce several different inversions, because there might be several numbers after it that are less than it (all of 1, 2, and 3 in the example). You may assume that the list has no duplicates.

Assume you are adding to the ArrayIntList class with following fields: 

public class ArrayIntList {
    private int[] elementData;
    private int size;

    // your code goes here
}
Type your solution here:


This is a partial class problem. Submit code that will become part of an existing Java class as described. You do not need to write the complete class, just the portion described in the problem.

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