Class Heapsort

java.lang.Object
  Heapsort

public class Heapsort
extends java.lang.Object

The Heapsort Java application illustrates a heapsort. Part of the implementation (the makeHeap and reheapifyDown methods) is left as a student exercise.

Java Source Code for this class (without makeHeap and reheapifyDown:

http://www.cs.colorado.edu/~main/applications/Heapsort.java

Constructor Summary

Heapsort()

Method Summary

static void	heapsort(int[] data, int n) This method cannot be used until the student implements makeHeap and reheapifyDown.
static void	main(java.lang.String[] args) The main method illustrates the use of a heapsort to sort a small array.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Heapsort

public Heapsort()

Method Detail

main

public static void main(java.lang.String[] args)

The main method illustrates the use of a heapsort to sort a small array. The String arguments (args) are not used in this implementation.

heapsort

public static void heapsort(int[] data,
                            int n)

This method cannot be used until the student implements makeHeap and reheapifyDown. Sort an array of integers from smallest to largest, using a heapsort algorithm.

Parameters:

data - the array to be sorted

n - the number of elements to sort, (from data[0] through data[n-1])

Precondition:

data has at least n elements.

Postcondition:

If n is zero or negative then no work is done. Otherwise, the elements of data have been rearranged so that data[0] <= data[1] <= ... <= data[n-1].

Throws:

java.lang.ArrayIndexOutOfBoundsException - Indicates that data has fewer than n elements.