Program Specification: A Stack is a simple container that is initially empty and need only support three simple operations:

isEmpty - reports true if the stack contains no values, otherwise reports false.

push value - adds value onto the stack.

pop - removes the most currently pushed value on the stack FIFO.

You are to extend your DynArray class to implement a stack which can hold double values and adheres to the following:

Mandatory Instance methods:

public int size() // returns the number of values which are currently on the stack

public boolean isEmpty() // returns true only if there are no values on the stack

public void push(double value) // add the specified value onto the stack

public double pop() // if the stack is not empty, // remove and returns the most currently pushd value on the stack // otherwise, // returns Double.NaN

public void stackDump() // print all of the values currenty on the stack, in the order that // they would be popd off of the stack

A Queue is a simple container that is initially empty and need only support three simple operations:

isEmpty - reports true if the queue contains no values, otherwise reports false.

que value - adds value into the queue.

deQue - removes the least currently queed value in the queue FILO.

You are to extend your DynArray class to implement a queue which can hold double values and adheres to the following:

Mandatory Instance methods:

public int size() // returns the number of values which are currently in the queue

public boolean isEmpty() // returns true only if there are no values in the queue

public void que(double value) // add the specified value into the queue

public double deQue() // if the queue is not empty, // remove and returns the least currently qued value in the queue // otherwise, / returns Double.NaN

public void queueDump() // print all of the values currenty in the queue, in the order that // they would be deQued from the queue

public class DynArray { private double[] array; private int size; private int nextIndex;

public int arraySize() { return this.size; }

public int elements() { return this.nextIndex; }

public double at(int index) { if(0 <= index && index < this.nextIndex) { return this.array[index]; } else { return Double.NaN; } }

public DynArray() { this.size = 1; this.array = new double[this.size]; this.nextIndex = 0; }

private void grow() { double[] growArray = new double[this.size * 2]; for(int i = 0; i < this.nextIndex; i++) { growArray[i] = this.array[i]; } this.array = growArray; this.size *= 2; }

private void shrink() { if(this.size/2 == this.nextIndex) { int shrink = this.size / 2; if(shrink <= 0) { shrink = 1; } double[] shrinkArray = new double[shrink]; for(int i = 0; i < this.nextIndex; i++) { shrinkArray[i] = this.array[i]; } this.array = shrinkArray; this.size = shrink; } }

public void insertAt(int index, double value) { if(0 <= index && index <= this.nextIndex) { if(this.nextIndex == this.size) { this.grow(); } for(int i = this.nextIndex; i > index; i--) { this.array[i] = this.array[i - 1]; } this.array[index] = value; this.nextIndex++; } }

public void insert(double value) { this.insertAt(this.nextIndex, value); }

public double removeAt(int index) { if(0 <= index && index < this.nextIndex) { double value = at(index); for(int i = index; i < this.nextIndex-1; i++) { this.array[i] = this.array[i + 1]; } this.shrink(); this.nextIndex--; return value; } else { return Double.NaN; } }

public double remove() { double value = at(this.nextIndex-1); this.nextIndex--; if(this.nextIndex == -1) { this.nextIndex = 0; } this.shrink(); return value; }

//accessor // prints the values of all occupied locations of the array to // the screen public void printArray() { for(int i = 0; i < this.nextIndex; i++) { System.out.println("array.at" + "(" + i + ")" + " " + this.array[i]); } } }