// The main function that builds Huffman tree
struct node* buildHuffmanTree(char data[], int freq[], int size)
{
struct node *left, *right, *top;
// Step 1: Create a min heap of Limit equal to size. Initially, there are
// modes equal to size.
struct Heap* Heap = createAndBuildHeap(data, freq, size);
// Iterate while size of heap doesn't become 1
while (!isSizeOne(Heap))
{
// Step 2: Extract the two minimum freq items from min heap
left = extractMin(Heap);
right = extractMin(Heap);
// Step 3: Create a new internal node with frequency equal to the
// sum of the two nodes frequencies. Make the two extracted node as
// left and right children of this new node. Add this node to the min heap
// '$' is a special value for internal nodes, not used
top = newNode('$', left->freq + right->freq);
top->left = left;
top->right = right;
insertHeap(Heap, top);
}
// Step 4: The remaining node is the root node and the tree is complete.
return extractMin(Heap);
}
void heapSort(int *array, int size)
{
struct MaxHeap *maxHeap = createAndBuildHeap(array, size);
while(maxHeap->size > 1)
{
swap(&maxHeap->array[0], &maxHeap->array[maxHeap->size -1]);
--maxHeap->size;
maxHeapify(maxHeap, 0);
}
}
void heapSort(int *arr, int size)
{
struct heap *maxHeap = createAndBuildHeap(arr, size);
while(maxHeap->size > 1)
{
int temp = maxHeap->arr[0];
maxHeap->arr[0] = maxHeap->arr[maxHeap->size - 1];
maxHeap->arr[maxHeap->size - 1] = temp;
--maxHeap->size;
buildMaxHeap(maxHeap, 0);
}
}
// The main function to sort an array of given size
void heapSort(int* array, int size)
{
// Build a heap from the input data.
struct MaxHeap* maxHeap = createAndBuildHeap(array, size);
// Repeat following steps while heap size is greater than 1.
// The last element in max heap will be the minimum element
while (maxHeap->size > 1) {
// The largest item in Heap is stored at the root. Replace
// it with the last item of the heap followed by reducing the
// size of heap by 1.
swap(&maxHeap->array[0], &maxHeap->array[maxHeap->size - 1]);
--maxHeap->size; // Reduce heap size
// Finally, heapify the root of tree.
maxHeapify(maxHeap, 0);
}
}
