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reorder

Language/Type: Java Collections Stacks and Queues
Author: Stuart Reges (on 2014/02/13)

Write a method reorder that takes a queue of integers as a parameter and that puts the integers into sorted (nondecreasing) order assuming that the queue is already sorted by absolute value. For example, suppose that a variable called q stores the following sequence of values: 

        front [1, 2, -2, 4, -5, 8, -8, 12, -15, 23] back

Notice that the values appear in sorted order if you ignore the sign of the numbers. The following call: 

        reorder(q);

should reorder the values so that the queue stores this sequence of values: 

        front [-15, -8, -5, -2, 1, 2, 4, 8, 12, 23] back

Notice that the values now appear in sorted order taking into account the sign of the numbers.

You are to use one stack as auxiliary storage to solve this problem. You may not use any other auxiliary data structures to solve this problem, although you can have as many simple variables as you like. You also may not solve the problem recursively. Your solution must run in O(n) time.

In writing your method, assume that you are using the Stack and Queue interfaces and the ArrayStack and LinkedQueue implementations discussed in lecture.

Write your solution to reorder below.

Type your solution here:


This is a method problem. Write a Java method as described. Do not write a complete program or class; just the method(s) above.

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