Implement an iterator that produces the moves for the Towers of Hanoi puzzle described in Worked Example 13.2. Provide methods hasMoreMoves and nextMove. The nextMove method should yield a string describing the next move. For example, the following code prints all moves needed to move five disks from peg 1 to peg 3:

A disk mover that moves a single disk from one peg to another simply has a nextMove method that returns a string Move disk from peg source to target A disk mover with more than one disk to move must work harder. It needs another DiskMover to help it move the first d – 1 disks. Then nextMove asks that disk mover for its next move until it is done. Then the nextMove method issues a command to move the dth disk. Finally, it constructs another disk mover that generates the remaining moves.
It helps to keep track of the state of the disk mover:
• BEFORE_LARGEST: A helper mover moves the smaller pile to the other peg.
• LARGEST: Move the largest disk from the source to the destination.
• AFTER_LARGEST: The helper mover moves the smaller pile from the other peg to the target.
• DONE: All moves are done.

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DiskMover mover = new DiskMover(5, 1, 3); while (mover.hasMoreMoves()) { } System.out.println (mover.next Move());