下面是修改后的代码：

#include<iostream>
#include<string.h>
#define MAXSIZE 100
using namespace std;
typedef struct
{//哈夫曼树结点的形式
    int weight;               //结点的权值
    int parent,lchild,rchild;  //结点的双亲、左孩子、右孩子的下标
}HTNode,*HuffmanTree;       //动态分配数组存储哈夫曼树
typedef char **HuffmanCode;   //定义编码表类型

int Search(char a[], char ch)
{//查找数组中字符ch所在的位置，返回数组下标，否则返回-1
    int flag = -1;
    for(int i = 0; i < (int)strlen(a); i++){
        if(a[i] == ch){
            flag = i;
            break;
        }
    }
    return flag;
}

void Sort(char a[], int b[], int len)
{//按ASCII码冒泡排序
    for(int i = 0; i < len; i++)
        for(int j = 0; j < len-1-i; j++){
            if(a[j] > a[j+1]){
                char ta;
                int tb;
                ta = a[j+1];
                a[j+1] = a[j];
                a[j] = ta;
                tb = b[j+1];
                b[j+1] = b[j];
                b[j] = tb;
            }
        }
}

void Select_min(HuffmanTree HT, int n, int &s1, int &s2)
{// 在HT[k](1≤k≤i-1）中选择两个其双亲域为0且权值最小的结点，并返回它们在HT中的序号s1和s2
    int m1 = 10086;
    int m2 = 10086;
    for(int i = 1; i <= n; i++){
        if(HT[i].parent == 0 && m1 > HT[i].weight){
            m2 = m1;
            m1 = HT[i].weight;
            s2 = s1;
            s1 = i;
            continue;
        }
        if(HT[i].parent == 0 && m2 > HT[i].weight){
            m2 = HT[i].weight;
            s2 = i;
            continue;
        }
    }
}

void CreateHuffmanTree(HuffmanTree &HT, int n, int b[])
{//构造哈夫曼树HT
    if(n <= 1) return;
    int m = 2 * n - 1;
    HT = new HTNode[m+1];
    for(int i=1; i<=m; i++){
        HT[i].parent = 0;
        HT[i].lchild=0;
        HT[i].rchild=0;
    }
    for(int i=1; i<=n; i++){
        HT[i].weight=b[i-1];
    }
    int s1=0,s2=0;
    for(int i=n+1;i<=m;i++){
        Select_min(HT,i-1,s1,s2);
        HT[s1].parent=i;
        HT[s2].parent=i;
        HT[i].lchild=s1;
        HT[i].rchild=s2;

      	// 计算新结点的权值为两个子节点权值之和
      	HT[i].weight = HT[s1].weight + HT[s2].weight;
    }
}

void CreateHuffmanCode(HuffmanTree HT, HuffmanCode &HC, int n)
{//从叶子到根逆向求每个字符的哈夫曼编码，存储在编码表HC中
    HC = new char*[n+1];
    char* cd = new char[n];
    cd[n-1] = '\0';
    for(int i=1; i<=n; i++){
        int start=n-1;
        int c=i;
        int f=HT[i].parent;
        while(f!=0){
            --start;
            if(HT[f].lchild==c)
                cd[start]='0';
            else
                cd[start]='1';
            c=f;
            f=HT[f].parent;
        }
        HC[i]=new char[n-start];
        strcpy(HC[i],&cd[start]);
    }
    delete[] cd;
}

void CharFrequency(char ch[], char a[], int b[], int &j)
{//统计词频
    for(int i=0;i<(int)strlen(ch);i++){
        for(int k=0;k<=26;k++){
            if(a[k]==ch[i]){
                b[k]++;
                break;
            }
            if(a[k]=='\0'){
                j++;
                a[k]=ch[i];
                b[k]++;
                break;
            }
        }
    }
}

void PrintHT(HuffmanTree HT)
{//输出哈夫曼树的存储结构的终态
    for(int i=1;i<=m;i++)
        cout<<i<<" "<<HT[i].weight<<" "<<HT[i].parent<<" "<<HT[i].lchild<<" "<<HT[i].rchild<<endl;
}

void PrintHC(HuffmanCode HC,char a[],int j)
{//输出每个字符的哈夫曼编码
    for(int i=1;i<=j;i++){
        if(i!=1)
            cout<<" ";
        cout<<a[i-1]<<":"<<HC[i];
    }
    cout<<endl;
}

int main() {
    char ch[] = "Hello World!";
    int len = strlen(ch);
    char a[MAXSIZE] = {'\0'};
    int b[MAXSIZE] = {0};
    int j = 0;

    CharFrequency(ch, a, b, j);

    Sort(a, b, j);

    HuffmanTree HT;
  	HuffmanCode HC;

  	CreateHuffmanTree(HT, j, b);
  	CreateHuffmanCode(HT, HC, j);

  	PrintHT(HT);
  	PrintHC(HC,a,j);

    return 0;
}

这是一个简单的实现了哈夫曼编码的程序，根据给定字符串统计字符频率，构建哈夫曼树，并生成哈夫曼编码。在主函数中添加了样例代码以演示使用方法。


内容由零声教学AI助手提供，问题来源于学员提问