如何用C语言从给定的Huffman树生成Huffman代码？

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

typedef struct {
    int weight;
    int parent, lchild, rchild;
} HuffmanNode, *HuffmanTree;

typedef char **HuffmanCode;

void Select(HuffmanTree HT, int k, int *s1, int *s2) {
    int min;
    for (int i = 1; i <= k; i++) {
        if (HT[i].parent == 0) {
            min = i;
            break;
        }
    }
    for (int j = i + 1; j <= k; j++) {
        if (HT[j].parent == 0 && HT[j].weight < HT[min].weight) {
            min = j;
        }
    }
    *s1 = min;
    for (int i = 1; i <= k; i++) {
        if (HT[i].parent == 0 && i != (*s1)) {
            min = i;
            break;
        }
    }
    for (int j = i + 1; j <= k; j++) {
        if (HT[j].parent == 0 && HT[j].weight < HT[min].weight && j != (*s1)) {
            min = j;
        }
    }
    *s2 = min;
}

void HuffmanCoding(HuffmanTree &HT, HuffmanCode &HC, int *w, int n) {
    int m = 2 * n - 1;
    HT = (HuffmanTree)malloc((m + 1) * sizeof(HuffmanNode));
    HC = (HuffmanCode)malloc((n + 1) * sizeof(char *));
    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 = w[i - 1];
    }
    for (int i = n + 1; i <= m; i++) {
        Select(HT, i - 1, &s1, &s2);
        HT[s1].parent = i;
        HT[s2].parent = i;
        HT[i].lchild = s1;
        HT[i].rchild = s2;
        HT[i].weight = HT[s1].weight + HT[s2].weight;
    }
    for (int i = 1; i <= n; i++) {
        int start = n;
        char cd[n];
        cd[n - 1] = '\0';
        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] = (char *)malloc((n - start) * sizeof(char));
        strcpy(HC[i], &cd[start]);
    }
}

int main() {
    int w[] = {5, 29, 7, 8, 14, 23, 3, 11};
    int n = sizeof(w) / sizeof(w[0]);
    HuffmanTree HT;
    HuffmanCode HC;
    HuffmanCoding(HT, HC, w, n);
    for (int i = 1; i <= n; i++) {
        printf("字符 %d 的 Huffman 编码是: %s\n", i, HC[i]);
    }
    return 0;
}