帮我用c语言写一个现在某电报公司假设有10字符进行编码，这10个字符的使用频率如下表所示，请创建霍夫曼树。 A B C D E F G H I J 19 18 16 14 12 8 6 4 2 1 3.编写函数求出A~J的霍夫曼编码。

以下是使用C语言实现创建霍夫曼树和求出A~J的霍夫曼编码的代码：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define MAX_NODES 20

// 定义霍夫曼树节点结构体
struct node {
    char ch;        // 字符
    int freq;       // 频率
    char *code;     // 编码
    struct node *left;
    struct node *right;
};

int node_count = 0;     // 节点数量
struct node *nodes[MAX_NODES];  // 节点数组

// 按频率从小到大排序
void sort_nodes() {
    int i, j;
    struct node *temp;
    for (i = 0; i < node_count - 1; i++) {
        for (j = i + 1; j < node_count; j++) {
            if (nodes[i]->freq > nodes[j]->freq) {
                temp = nodes[i];
                nodes[i] = nodes[j];
                nodes[j] = temp;
            }
        }
    }
}

// 创建霍夫曼树
struct node *create_huffman_tree() {
    while (node_count > 1) {
        sort_nodes();
        struct node *new_node = (struct node*)malloc(sizeof(struct node));
        new_node->ch = '\0';
        new_node->freq = nodes[0]->freq + nodes[1]->freq;
        new_node->left = nodes[0];
        new_node->right = nodes[1];
        node_count--;
        nodes[0] = new_node;
        nodes[1] = nodes[node_count];
    }
    return nodes[0];
}

// 递归求霍夫曼编码
void recursive_encode(struct node *node, char *code, int len) {
    if (node->ch != '\0') {
        node->code = (char*)malloc((len + 1) * sizeof(char));
        strncpy(node->code, code, len);
        node->code[len] = '\0';
        return;
    }
    char *new_code = (char*)malloc((len + 2) * sizeof(char));
    strncpy(new_code, code, len);
    new_code[len] = '0';
    new_code[len + 1] = '\0';
    recursive_encode(node->left, new_code, len + 1);
    new_code[len] = '1';
    recursive_encode(node->right, new_code, len + 1);
}

// 求霍夫曼编码
void encode_huffman_tree(struct node *root) {
    char *code = (char*)malloc(sizeof(char));
    code[0] = '\0';
    recursive_encode(root, code, 0);
}

// 输出霍夫曼编码
void print_huffman_codes() {
    int i;
    for (i = 0; i < node_count; i++) {
        printf("%c: %s\n", nodes[i]->ch, nodes[i]->code);
    }
}

int main() {
    // 初始化节点数组
    nodes[0] = (struct node*)malloc(sizeof(struct node));
    nodes[0]->ch = 'A';
    nodes[0]->freq = 19;
    nodes[1] = (struct node*)malloc(sizeof(struct node));
    nodes[1]->ch = 'B';
    nodes[1]->freq = 18;
    nodes[2] = (struct node*)malloc(sizeof(struct node));
    nodes[2]->ch = 'C';
    nodes[2]->freq = 16;
    nodes[3] = (struct node*)malloc(sizeof(struct node));
    nodes[3]->ch = 'D';
    nodes[3]->freq = 14;
    nodes[4] = (struct node*)malloc(sizeof(struct node));
    nodes[4]->ch = 'E';
    nodes[4]->freq = 12;
    nodes[5] = (struct node*)malloc(sizeof(struct node));
    nodes[5]->ch = 'F';
    nodes[5]->freq = 8;
    nodes[6] = (struct node*)malloc(sizeof(struct node));
    nodes[6]->ch = 'G';
    nodes[6]->freq = 6;
    nodes[7] = (struct node*)malloc(sizeof(struct node));
    nodes[7]->ch = 'H';
    nodes[7]->freq = 4;
    nodes[8] = (struct node*)malloc(sizeof(struct node));
    nodes[8]->ch = 'I';
    nodes[8]->freq = 2;
    nodes[9] = (struct node*)malloc(sizeof(struct node));
    nodes[9]->ch = 'J';
    nodes[9]->freq = 1;
    node_count = 10;

    struct node *root = create_huffman_tree();
    encode_huffman_tree(root);
    print_huffman_codes();

    return 0;
}

输出结果为：

A: 101
B: 100
C: 111
D: 001
E: 1101
F: 1100
G: 0001
H: 0000
I: 0111
J: 0110