FilesExpand file tree

 master

/

HeapSort.java

Copy path

Blame

More file actions

Blame

More file actions

Latest commit

 

History

History

History

74 lines (62 loc) · 1.59 KB

 master

/

HeapSort.java

Copy path

Top

File metadata and controls

• Code
• Blame

74 lines (62 loc) · 1.59 KB

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

64

65

66

67

68

69

70

71

72

73

74

// Java program for implementation of Heap Sort

public class HeapSort

{

public void sort(int arr[])

{

int n = arr.length;

// Build heap (rearrange array)

for (int i = n / 2 - 1; i >= 0; i--)

heapify(arr, n, i);

// One by one extract an element from heap

for (int i=n-1; i>=0; i--)

{

// Move current root to end

int temp = arr[0];

arr[0] = arr[i];

arr[i] = temp;

// call max heapify on the reduced heap

heapify(arr, i, 0);

}

}

// To heapify a subtree rooted with node i which is

// an index in arr[]. n is size of heap

void heapify(int arr[], int n, int i)

{

int largest = i; // Initialize largest as root

int l = 2*i + 1; // left = 2*i + 1

int r = 2*i + 2; // right = 2*i + 2

// If left child is larger than root

if (l < n && arr[l] > arr[largest])

largest = l;

// If right child is larger than largest so far

if (r < n && arr[r] > arr[largest])

largest = r;

// If largest is not root

if (largest != i)

{

int swap = arr[i];

arr[i] = arr[largest];

arr[largest] = swap;

// Recursively heapify the affected sub-tree

heapify(arr, n, largest);

}

}

/* A utility function to print array of size n */

static void printArray(int arr[])

{

int n = arr.length;

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

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

System.out.println();

}

// Driver program

public static void main(String args[])

{

int arr[] = {12, 11, 13, 5, 6, 7};

int n = arr.length;

HeapSort ob = new HeapSort();

ob.sort(arr);

System.out.println("Sorted array is");

printArray(arr);

}

}