哈夫曼树，c语言版！

/*
 哈夫曼树
*/
#include<stdio.h>
#include<stdio.h>
#define n 5  //叶子结点个数
#define m 2*n-1 //hufftree的结点个数

//定义构造hufftree的结构体
typedef struct
{
 char data;
 int weight;
 int parent, lchild, rchild;
}huffnode;

//定义输出哈夫曼编码的结构体
typedef struct
{
 char path[m];
 int start;
}huffcode;

//构造哈夫曼树
void create_hufftree(huffnode tree[]);
//编码
void create_huffcode(huffnode tree[]);
//打印函数
void print_hufftree(huffnode tree[]);

int main()
{
 huffnode tree[m+1]; //0号单元不用
 create_hufftree(tree);
 print_hufftree(tree);
 
 create_huffcode(tree);
 //printf("2");
 return 0;
}

void create_hufftree(huffnode tree[])
{
 int i, k, l, r, small1, small2;
 for(i=1; i<=m; i++)  //对每个结点进行初始化
 {
  tree[i].parent = tree[i].lchild = tree[i].rchild = 0;
  tree[i].data =' ';
 }
 for(i=1; i<=n; i++)  //输入n个结点的信息
 {
  if(i!=1) getchar();
  printf("The value of %dth element: ", i);
  scanf("%c", &tree[i].data);
  printf("The weight of %dth element: ", i);
  scanf("%d", &tree[i].weight);
 }
 for(i=n+1; i<=m; i++) //构造huffman树
 {
  small1 = small2 = 32767;
  l = r = 0;   //l和r为最小权重的两个结点位置
  for(k=1; k<=i-1; k++)
  {
   if(tree[k].parent == 0)
    if(tree[k].weight<small1)
    {
     small2 = small1;
     r = l;
     small1 = tree[k].weight;
     l = k;
    }
    else if(tree[k].weight<small2)
    {
     small2 = tree[k].weight;
     r = k;
    } 
  }
  tree[l].parent = i;
  tree[r].parent = i;
  tree[i].weight = tree[l].weight + tree[r].weight;
  tree[i].lchild = l;
  tree[i].rchild = r;
 }
}

void create_huffcode(huffnode tree[])
{
 int i, k, mid, p;
 huffcode hcd[n], node;
 printf("1");
 for(i=1; i<=n; i++)
 {
  //printf("3");
  node.start = n+1;
  mid = i;
  p = tree[i].parent;
  //printf("assas");
  while(p!=0)
  { 
   //printf("4");
   if(tree[p].lchild == mid)
    node.path[node.start] = '0';
   else
    node.path[node.start] = '1';
   node.start--;
   mid = p;
   p = tree[p].parent;
  }
  
  hcd[i] = node;
 }
 printf("Output Huffman code: ");
 for(i=1; i<=n; i++)
 {
  printf("%c:", tree[i].data);
  for(k=hcd[i].start; k<=n; k++)
   printf("%c", hcd[i].path[k]);
  printf(" ");
 }
}

/*
void create_huffcode(huffnode tree[])
{
 int i, k, mid, p;
 huffcode hcd[5], node;
 for(i=1; i<=5; i++)
 {
  node.start = 6;
  mid = i;
  p = tree[i].parent;
  while(p!=0)
  {
   if(tree[p].lchild == mid)
   node.path[--node.start]='0';
   else node.path[--node.start]='1';
   mid = p;
   p = tree[p].parent;
  }
  hcd[i] = node;
 }
 
 printf("Output Huffman code: ");
 for(i=1; i<=n; i++)
 {
  printf("%c:", tree[i].data);
  for(k=hcd[i].start; k<=n; k++)
   printf("%c", hcd[i].path[k]);
  printf(" ");
 }
 
}*/
void print_hufftree(huffnode tree[]) /*输出整棵哈夫曼树*/
{
 int i;
 printf("huffman tree: ");
 printf("i Vlue Parent Lchild Richild Weight ");
 for(i=m; i>=1; i--)
 {
  printf("%d ", i);
  printf("%c ", tree[i].data);
  printf("%d ", tree[i].parent);
  printf("%d ", tree[i].lchild);
  printf("%d ", tree[i].rchild);
  printf("%d ", tree[i].weight);
  printf(" ");

 }
}