92 lines
2.1 KiB
C
92 lines
2.1 KiB
C
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#include <stdio.h>
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#include <stdlib.h>
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typedef struct Node
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{
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int weight;
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struct Node *lChild;
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struct Node *rChild;
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} Node;
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// 比较函数，用于优先队列
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int compare(const void *a, const void *b)
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{
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return (*(Node **)a)->weight - (*(Node **)b)->weight;
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}
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// 创建新的节点
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Node *createNode(int weight)
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{
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Node *newNode = (Node *)malloc(sizeof(Node));
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newNode->weight = weight;
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newNode->lChild = NULL;
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newNode->rChild = NULL;
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return newNode;
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}
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// 构建哈夫曼树
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Node *createHuffman(int *weights, int size)
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{
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Node **nodeArray = (Node **)malloc(size * sizeof(Node *));
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// 初始化节点数组
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for (int i = 0; i < size; i++)
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{
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nodeArray[i] = createNode(weights[i]);
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printf("%d,", nodeArray[i]->weight);
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}
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qsort(nodeArray, size, sizeof(Node *), compare);
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for (int i = 0; i < size; i++)
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{
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printf("%d-", nodeArray[i]->weight);
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}
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// 使用qsort实现优先队列
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for (int i = size; i > 1; i--)
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{
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qsort(nodeArray, i, sizeof(Node *), compare);
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// 找到最右边两个节点
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Node *left = nodeArray[i - 1];
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Node *right = nodeArray[i - 2];
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// 创建新父节点
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Node *parent = createNode(left->weight + right->weight);
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parent->lChild = left;
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parent->rChild = right;
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// 将新节点放入数组中
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nodeArray[i - 2] = parent;
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}
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Node *root = nodeArray[0];
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free(nodeArray);
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return root;
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}
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// 前序遍历输出
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void output(Node *head)
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{
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if (head == NULL)
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{
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return;
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}
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printf("%d\n", head->weight);
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output(head->lChild);
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output(head->rChild);
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}
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// 释放树的内存
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void freeTree(Node *root)
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{
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if (root == NULL)
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{
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return;
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}
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freeTree(root->lChild);
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freeTree(root->rChild);
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free(root);
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}
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int main()
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{
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int weights[] = {2, 18, 9, 3, 7,25};
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int size = sizeof(weights) / sizeof(weights[0]);
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Node *huffmanTree = createHuffman(weights, size);
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printf("前序遍历halftree:\n");
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output(huffmanTree);
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// 释放树的内存
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freeTree(huffmanTree);
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return 0;
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}
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