Build a huffman tree using min-heap - c

Question

I came across some problems when building a huffman tree. When building the huffman tree, I use min-heap to implement. And I think the code of min-heap is work well, but when I run the building-huffman-Tree code, the error appears. I have dug into it for a long time, but I have no means to solve it.Hope someone help me sovle my problem.The code is following:
#include <stdio.h>
#include <stdlib.h>
#define MaxSize 100
#define MaxData NULL
// Huffman tree的建树过程用最小堆时因为每次都可以挑出最小的两个元素组成
typedef struct TreeNode {
int weight;
struct TreeNode *left;
struct TreeNode *right;
}HuffmanTree;
typedef struct HeapStruct {
HuffmanTree *Elements[MaxSize+1]; // an array
int Size; // the number of item in array
int Capacity; /* the capacity of heap */
}MinHeap;
MinHeap *Create()
{ // create a empty heap
MinHeap *H;
H = (MinHeap *)malloc(sizeof(MinHeap));
H->Elements[0] = NULL;
H->Size = 0;
H->Capacity = MaxSize;
return H;
}
int isFull(MinHeap *H)
{ // judge the heap full or not
return (H->Size == MaxSize);
}
int isEmpty(MinHeap *H)
{ // judge the heap empty or not
return (H->Size == 0);
}
void Add(MinHeap *H, int item)
{ // add item to the array
if( isFull(H) )
{
printf("the heap is full.\n");
return;
}
HuffmanTree *T;
T = (HuffmanTree *)malloc(sizeof(HuffmanTree));
T->weight = item;
H->Elements[++(H->Size)] = T;
return;
}
void Insert(MinHeap *H, HuffmanTree *item)
{ // insert item
int i;
if( isFull(H) )
{
printf("the heap is full.\n");
return;
}
i = ++(H->Size);
for(; (H->Elements[i/2]->weight)>(item->weight);i/=2)
H->Elements[i] = H->Elements[i/2];
H->Elements[i] = item;
}
HuffmanTree *DeleteMin(MinHeap *H)
{ // delete item of the heap
int Parent, Child;
HuffmanTree *MinValueNode, *tempNode;
if( isEmpty(H) )
{
printf("the heap is empty.\n");
return NULL;
}
MinValueNode = H->Elements[1];
tempNode = H->Elements[H->Size--];
for(Parent=1; Parent*2<=H->Size; Parent=Child)
{
Child = Parent * 2;
if( (Child != H->Size) && (H->Elements[Child]->weight > H->Elements[Child+1]->weight) )
Child++;
if( tempNode->weight <= H->Elements[Child]->weight )
break;
else
H->Elements[Parent] = H->Elements[Child];
}
H->Elements[Parent] = tempNode;
return MinValueNode;
}
void PercDown(MinHeap *H, int i)
{ // adjustment of the heap
int Parent, Child;
HuffmanTree *temp;
temp = H->Elements[i];
for(Parent=i; Parent*2<=H->Size; Parent=Child)
{
Child = Parent * 2;
if( (Child != H->Size) && (H->Elements[Child]->weight > H->Elements[Child+1]->weight) )
Child++; // Child point to the min
if( temp->weight <= H->Elements[Child]->weight )
break;
else
H->Elements[Parent] = H->Elements[Child];
}
H->Elements[Parent] = temp;
}
void BuildMinHeap(MinHeap *H)
{
int i;
for(i=H->Size/2; i>0; i--)
PercDown(H, i);
return;
}
HuffmanTree *Huffman(MinHeap *H)
{ /* Assuming that H->Size weight hava existed in H->Elements[]->weight */
int i;
HuffmanTree *T;
BuildMinHeap( H ); // adjustment
for(i=1; i<H->Size; i++) // merge H->Size-1
{
T = (HuffmanTree *)malloc(sizeof(HuffmanTree));
T->left = DeleteMin( H );
T->right = DeleteMin( H );
T->weight = T->left->weight + T->right->weight;
Insert(H, T);
}
T = DeleteMin( H );
return T;
}
void print_heap(MinHeap *H)
{
if( isEmpty(H) )
{
printf("the heap is empty.\n");
return;
}
for(int i=1; i<=H->Size; i++)
printf("%d ", H->Elements[i]->weight);
printf("\n");
}
void print_tree(HuffmanTree *T)
{
if( T )
{
print_tree(T->left);
printf("%d ", T->weight);
print_tree(T->right);
}
return;
}
int main()
{
MinHeap *heap;
HuffmanTree *HT, *T;
heap = Create();
int x;
printf("please input data:\n");
scanf("%d", &x);
while( x )
{
Add(heap, x);
scanf("%d", &x);
}
printf("original items:\n");
print_heap( heap );
printf("the item number of heap%d\n", heap->Size);
BuildMinHeap(heap);
print_heap( heap );
HT = DeleteMin( heap );
printf("删除的结点的值为%d\n", HT->weight);
print_heap( heap );
HT = Huffman( heap );
print_tree( HT );
return 0;
}