MinPQ.java:

import stdlib.*;

import java.util.Comparator;

import java.util.Iterator;

import java.util.NoSuchElementException;

public class MinPQ> implements Iterable {

private K[] pq; // store items at indices 1 to N

private int N; // number of items on priority queue

private Comparator super K> comparator; // optional comparator

// helper function to double the size of the heap array

@SuppressWarnings("unchecked")

private void resize(int capacity) {

if (capacity

K[] temp = (K[]) new Comparable[capacity];

for (int i = 1; i

pq = temp;

}

@SuppressWarnings("unchecked")

/** Create an empty priority queue with the given initial capacity, using the given comparator. */

public MinPQ(int initCapacity, Comparator super K> comparator) {

pq = (K[]) new Comparable[initCapacity + 1];

N = 0;

this.comparator = comparator;

}

/** Create an empty priority queue with the given initial capacity. */

public MinPQ(int initCapacity) { this(initCapacity, null); }

/** Create an empty priority queue using the given comparator. */

public MinPQ(Comparator super K> comparator) { this(1, comparator); }

/** Create an empty priority queue. */

public MinPQ() { this(1, null); }

/**

* Create a priority queue with the given items.

* Takes time proportional to the number of items using sink-based heap construction.

*/

public MinPQ(K[] keys) {

this(keys.length, null);

N = keys.length;

for (int i = 0; i

pq[i+1] = keys[i];

for (int k = N/2; k >= 1; k--)

sink(k);

//assert isMinHeap();

}

/** Is the priority queue empty? */

public boolean isEmpty() { return N == 0; }

/** Return the number of items on the priority queue. */

public int size() { return N; }

/**

* Return the smallest key on the priority queue.

* @throws java.util.NoSuchElementException if the priority queue is empty.

*/

public K min() {

if (isEmpty()) throw new NoSuchElementException("Priority queue underflow");

return pq[1];

}

/** Add a new key to the priority queue. */

public void insert(K x) {

// double size of array if necessary

if (N >= pq.length - 1) resize(2 * pq.length);

// add x, and percolate it up to maintain heap invariant

pq[++N] = x;

swim(N);

//assert isMinHeap();

}

/**

* Delete and return the smallest key on the priority queue.

* @throws java.util.NoSuchElementException if the priority queue is empty.

*/

public K delMin() {

if (isEmpty()) throw new NoSuchElementException("Priority queue underflow");

exch(1, N);

K min = pq[N--];

sink(1);

pq[N+1] = null; // avoid loitering and help with garbage collection

if ((N > 0) && (N == (pq.length - 1) / 4)) resize(pq.length / 2);

//assert isMinHeap();

return min;

}

/* *********************************************************************

* Helper functions to restore the heap invariant.

**********************************************************************/

private void swim(int k) {

while (k > 1 && greater(k/2, k)) {

exch(k, k/2);

k = k/2;

}

}

private void sink(int k) {

while (2*k

int j = 2*k;

if (j

if (!greater(k, j)) break;

exch(k, j);

k = j;

}

}

/* *********************************************************************

* Helper functions for compares and swaps.

**********************************************************************/

private boolean greater(int i, int j) {

if (comparator == null) {

return pq[i].compareTo(pq[j]) > 0;

}

else {

return comparator.compare(pq[i], pq[j]) > 0;

}

}

private void exch(int i, int j) {

K swap = pq[i];

pq[i] = pq[j];

pq[j] = swap;

}

// is pq[1..N] a min heap?

private boolean isMinHeap() {

return isMinHeap(1);

}

// is subtree of pq[1..N] rooted at k a min heap?

private boolean isMinHeap(int k) {

if (k > N) return true;

int left = 2*k, right = 2*k + 1;

if (left

if (right

return isMinHeap(left) && isMinHeap(right);

}

/* *********************************************************************

* Iterator

**********************************************************************/

/**

* Return an iterator that iterates over all of the keys on the priority queue

* in ascending order.

*

* The iterator doesn't implement remove() since it's optional.

*/

public Iterator iterator() { return new HeapIterator(); }

private class HeapIterator implements Iterator {

// create a new pq

private MinPQ copy;

// add all items to copy of heap

// takes linear time since already in heap order so no keys move

public HeapIterator() {

if (comparator == null) copy = new MinPQ(size());

else copy = new MinPQ(size(), comparator);

for (int i = 1; i

copy.insert(pq[i]);

}

public boolean hasNext() { return !copy.isEmpty(); }

public void remove() { throw new UnsupportedOperationException(); }

public K next() {

if (!hasNext()) throw new NoSuchElementException();

return copy.delMin();

}

}

void showHeap() {

for (int i = 1; i

StdOut.print (pq[i] + " ");

StdOut.println ();

}

/**

* A test client.

*/

public static void main(String[] args) {

MinPQ pq = new MinPQ(100);

StdIn.fromString ("10 20 30 40 50 - - - 05 25 35 - - - 70 80 05 - - - - ");

while (!StdIn.isEmpty()) {

StdOut.print ("pq: "); pq.showHeap();

String item = StdIn.readString();

if (item.equals("-")) StdOut.println("min: " + pq.delMin());

else pq.insert(item);

GraphvizBuilder.binaryHeapToFile (pq.pq, pq.N);

}

StdOut.println("(" + pq.size() + " left on pq)");

}

}

TestFinalAnswer.java:

package finalanswer;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.Random;

import stdlib.StdIn;

import stdlib.StdOut;

public class TestFinalAnswer {

public static > boolean isSorted(Item[] a) {

for (int i = 0; i

if (a[i].compareTo(a[i+1]) > 0) return false;

}

return true;

}

public static void main(String[] args) {

StdOut.println("*** " + FinalAnswer.yourName() + " ***");

StdOut.println();

Integer[] array = new Integer[12];

Random r = new Random();

for (int i = 0; i

array[i] = r.nextInt(1000);

}

StdOut.println("Array before sorting: " + Arrays.toString(array));

FinalAnswer.minpqSort(array);

StdOut.println("Array after sorting: " + Arrays.toString(array));

StdOut.println("Array is sorted: " + isSorted(array));

StdOut.println();

Queue queue = new Queue();

queue.enqueue("first");

queue.enqueue("second");

queue.enqueue("third");

queue.enqueue("fourth");

StdOut.println("Queue before reversing: " + queue);

FinalAnswer.reverseQueue(queue);

StdOut.println("Queue after reversing: " + queue);

StdOut.println();

double[] frequencies = {110.0, 110.0*1.224, 110.0*1.224*1.224};

ArrayList risingChords = FinalAnswer.createRisingChordList(0.2, frequencies, 10);

for (Chord risingChord: risingChords) {

StdOut.println("Playing: " + risingChord);

risingChord.play();

}

StdOut.println();

ArrayList ctaTrains = new ArrayList();

StdIn.fromFile("data/CTAdata.txt");

while (!StdIn.isEmpty()) {

int runNumber = StdIn.readInt();

String lineColor = StdIn.readString();

String nextStation = StdIn.readString();

String arrivalTime = StdIn.readString();

ctaTrains.add(new CTATrain(runNumber, lineColor, nextStation, arrivalTime));

}

StdOut.println("--- Trains before sorting ---");

for (CTATrain ctaTrain: ctaTrains) {

StdOut.println(ctaTrain);

}

StdOut.println();

ctaTrains.sort(null);

StdOut.println("--- Trains after sorting by run number ---");

for (CTATrain ctaTrain: ctaTrains) {

StdOut.println(ctaTrain);

}

StdOut.println();

ctaTrains.sort((CTATrain t1, CTATrain t2) -> (t1.getArrivalTime().compareTo(t2.getArrivalTime())));

StdOut.println("--- Trains after sorting by arrival time ---");

for (CTATrain ctaTrain: ctaTrains) {

StdOut.println(ctaTrain);

}

StdOut.println();

StdOut.println("=== " + FinalAnswer.yourName() + " ===");

}

}

Need help with a Java problem: Instructions 1. In Eclipse, create a package called finalanswer. 2. Copy and place into the package the file TestFinalAnswer.iava provided below. 3. In the package, create a class called FinalAnswer. All of the static methods you are asked to write will go in this class. Priority queue Provided below, you will find a class MinPO, which implements a minimum priority queue. You are to use it to define in the EinalAnswer class a generic sort method with the signature: public static