Java program for heap sort

import java.util.Scanner;

public class HeapSort {

public static void main(String args[]) {

int n;

int num[];

Scanner scan = new Scanner(System.in);

System.out.println("\nEnter the number of elements :");

n = Integer.parseInt(scan.nextLine());

System.out.println("Enter the numbers :");

num = new int[n];

for(int i=0; i<n; i++) {

num[i] = Integer.parseInt(scan.nextLine());

}

for(int i=n; i>1; i--) {

HeapSort(num, i - 1);

}

System.out.println("\nHeap sorted list are");

for(int i=0; i<n; i++) {

System.out.print(" " + num[i]);

}

}

private static void HeapSort(int array[], int bound) {

int left, right, middle, root, temp;

root = (bound-1) / 2;

for(int i=root; i>=0; i--) {

for(int j=root; j>=0; j--) {

left = (2*j) + 1;

right = (2*j) + 2;

if((left <= bound) && (right <= bound)) {

if(array[right] >= array[left])

middle = right;

else

middle = left;

}

else {

if(right > bound)

middle = left;

else

middle = right;

}

if(array[j] < array[middle]) {

temp = array[j];

array[j] = array[middle];

array[middle] = temp;

}

}

}

temp = array[0];

array[0] = array[bound];

array[bound] = temp;

}

}

OUTPUT:-

C:\Users\saty\Desktop>javac HeapSort.java

C:\Users\saty\Desktop>java HeapSort 

Enter the number of elements :

8

Enter the numbers :

45

8

72

34

5

1

9

34

Heap sorted list are

 1 5 8 9 34 34 45 72