哈夫曼树的构建

/*哈夫曼树的构建*/
#define MAXVALUE 10000
#define MAXLEAF 30
#define MAXNODE MAXLEAF*2-1

typedef struct 
{
	int weight;
	int parent;
	int lchild;
	int rchild;
}hnode , huffmantree[MAXNODE];

void crthuffmantree(huffmantree ht,int w[],int n)
{
	int i,j,m1,m2,x1,x2;

	for(i=0;i<2*n-1,i++)//ht 初始化
	{
		ht[i].weight=0;
		ht[i].lchild=-1;
		ht[i].rchild=-1;
		ht[i].parent=-1;
	}
	for(i=0;i<n;i++) ht[i].weight=w[i]; //赋予n个叶子结点的权值

	for(i=0;i<n-1;i++)
	{
	m1=m2=MAXVALUE;
	x1=x2=0;
	for(j=0;j<n+i;j++)
	{
		if(ht[j].weight<m1&&ht[j].parent==-1)
		{
			m2=m1;x2=x1;x1=j;
			m1=ht[j].weight;
		}else if(ht[j].weight<m2&&ht[j].parent==-1)
		{
			m2=ht[j].weight;
			x2=j;
		}
	}
	ht[x1].parent=n+i;	ht[x2].parent=n+i;
	ht[n+i].weight=ht[x1].weight+ht[x2].weight;
	ht[n+i].lchild=x1,ht[n+i].rchild=x2;	
	}
}