programming-for-dummies

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Using Heap Sort
Initially, the heap sort algorithm may seem complicated because you need to
create a heap data structure, copy and sort values among nodes, and delete
nodes while you remove values and store them back in a sorted list.
Although you can create a heap data structure by using a linked list, a much
simpler method is to create a heap data structure by using an array, as
shown in Figure 1-8.
The first array element represents the root node, the next two elements represent
the child nodes of the root, and so on. Rather than manipulate a
linked list as a heap, it’s much simpler to rearrange values stored in an array,
as shown in Figure 1-9. Because arrays are easy to implement in any programming
language, the heap sort algorithm is also easy to implement.
Although slightly more complicated than bubble sort or selection sort, the
heap sort algorithm offers faster performance.
94
Root node
46
74
Level 1
21
32
50
68
Level 2
9 Level 3
A heap
Root node
Figure 1-8:
An array
can mimic a
heap data
structure.
94 46 74 21 32 50 68 9
Level 1 Level 2 Level 3