哈夫曼树的建立

Posted 2020-10-15 marybubble

闲暇的夜晚， 写个哈夫曼树练练笔。

 

 

#include<iostream>
#include<cstring>
#include<cstdlib>
#include<algorithm>
typedef struct
{
 char data;
 int w,parent, lchild, rchild;
 int use;
}HFNode,*HuffmanTree;
char N[100];    //用以保存结点的data
int w[100];     //权值
typedef struct
{
 int s1, s2;
}Mincode;       //存储最小权值与次小权值结点的下标
int cmpw1(HuffmanTree HC,int q)      //找出最小权值的结点的下标
{
 int i,min = 666666,pos=0;
 for (i = 0; i < q; i++)
 {
  if ((HC + i)->w < min&& (HC + i)->use==1)
  {
   min = (HC + i)->w;
   pos = i;
  }
 }
 return pos;
}
int cmpw2(HuffmanTree HC, int q,int s)  //找出次小权值的结点的下标
{
 int i, min = 666666, pos = 0;
 for (i = 0; i < q; i++)
 {
  if ((HC + i)->w < min&&i!=s&& (HC + i)->use == 1)
  {
   min = (HC + i)->w;
   pos = i;
  }
 }
 return pos;

}
Mincode Select(HuffmanTree HC, int q)
{
 Mincode code;
 code.s1=cmpw1(HC, q);
 code.s2 = cmpw2(HC, q, code.s1);
 return code;
}
int main()
{
 HuffmanTree HC;
 Mincode code;
 printf("Input N:\n");
 scanf("%s",N);
 int n = strlen(N);
 int m = 2 * n - 1;
 int i = 0;
 HC = (HuffmanTree)malloc(m * sizeof(HFNode));
 printf("Input W:\n");
 for (int i = 0; i < n; i++)
  scanf("%d",&w[i]);
 for (i = 0; i < n; i++)      //初始化
 {
  (HC + i)->data = N[i];
  (HC + i)->w = w[i];
  (HC + i)->parent = 0;
  (HC + i)->lchild = 0;
  (HC + i)->rchild = 0;
  (HC + i)->use = 1;
 }
 for (; i < m; i++)
 {
  (HC + i)->data =‘0‘;
  (HC + i)->w =0;
  (HC + i)->parent = 0;
  (HC + i)->lchild = 0;
  (HC + i)->rchild = 0;
  (HC + i)->use = 1;
 }
 for (int i = n; i < m; i++)   //构造哈夫曼树
 {
  code=Select(HC, i);
  printf("%d %d\n",code.s1,code.s2);
  (HC + code.s1)->use = 0;
  (HC + code.s2)->use = 0;
  (HC + code.s1)->parent = i;
  (HC + code.s2)->parent = i;
  (HC + i)->lchild = code.s1;
  (HC + i)->rchild = code.s2;
  (HC + i)->w = (HC + code.s1)->w+(HC+code.s2)->w;
 }
 printf("data\tw\tparent\tlchild\trchild\n");
 for (int i = 0; i < m; i++)
  printf("%c\t%d\t%d\t%d\t%d\t\n",(HC+i)->data,(HC+i)->w,(HC+i)->parent,(HC+i)->lchild,(HC+i)->rchild);
 return 0;
}