构造哈夫曼树 代码 C语言

以下是用C语言实现构造哈夫曼树的代码示例：

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

// 定义哈夫曼树结点的结构体
typedef struct Node {
    int weight;
    struct Node *left;
    struct Node *right;
} Node;

// 创建一个新的哈夫曼树结点
Node* createNode(int weight) {
    Node* newNode = (Node*)malloc(sizeof(Node));
    newNode->weight = weight;
    newNode->left = NULL;
    newNode->right = NULL;
    return newNode;
}

// 构造哈夫曼树
Node* buildHuffmanTree(int weights[], int n) {
    // 创建一个存放哈夫曼树结点的数组
    Node** nodes = (Node**)malloc(n * sizeof(Node*));
    for (int i = 0; i < n; i++) {
        nodes[i] = createNode(weights[i]);
    }

    // 不断合并权重最小的两个结点，直到只剩下一个结点，即根结点
    while (n > 1) {
        // 找到权重最小的两个结点
        int min1 = 0, min2 = 1;
        if (nodes[min1]->weight > nodes[min2]->weight) {
            int temp = min1;
            min1 = min2;
            min2 = temp;
        }
        for (int i = 2; i < n; i++) {
            if (nodes[i]->weight < nodes[min1]->weight) {
                min2 = min1;
                min1 = i;
            } else if (nodes[i]->weight < nodes[min2]->weight) {
                min2 = i;
            }
        }

        // 创建一个新的结点，权重为两个最小结点的权重之和
        Node* newNode = createNode(nodes[min1]->weight + nodes[min2]->weight);
        newNode->left = nodes[min1];
        newNode->right = nodes[min2];

        // 将新结点放入数组中
        nodes[min1] = newNode;

        // 删除已合并的两个结点
        for (int i = min2; i < n - 1; i++) {
            nodes[i] = nodes[i + 1];
        }

        n--;
    }

    // 返回根结点
    return nodes[0];
}

// 打印哈夫曼树的编码
void printHuffmanCodes(Node* root, int code[], int top) {
    // 如果是叶子结点，则打印编码
    if (root->left == NULL && root->right == NULL) {
        printf("Character: %c, Code: ", root->weight);
        for (int i = 0; i < top; i++) {
            printf("%d", code[i]);
        }
        printf("\n");
    }

    // 左子树添加0，右子树添加1
    code[top] = 0;
    printHuffmanCodes(root->left, code, top + 1);

    code[top] = 1;
    printHuffmanCodes(root->right, code, top + 1);
}

int main() {
    int weights[] = {5, 9, 12, 13, 16, 45};
    int n = sizeof(weights) / sizeof(weights[0]);

    Node* root = buildHuffmanTree(weights, n);

    int code[100];
    int top = 0;
    printHuffmanCodes(root, code, top);

    return 0;
}