Have the PriorityQueue support decreaseKey as follows: Define a nested class that implements PriorityQueue.Position. The binary heap will be represented by an array of objects, in which each object...

Have the PriorityQueue support decreaseKey as follows: Define a nested class that implements PriorityQueue.Position. The binary heap will be represented by an array of objects, in which each object stores a data item and its index. Each PriorityQueue.Position object stores a reference back to the corresponding object in the array.