尝试用c语言编写一个算法来计算哈夫曼树的wpl(带权路径长度)。

好的，下面是一个用C语言实现的计算哈夫曼树WPL的算法：

#include <stdio.h>
#include <stdlib.h>
#define MAX 100

typedef struct node{
    int data;
    int weight;
    int parent;
    int leftChild;
    int rightChild;
}HuffmanNode;

void createHuffmanTree(HuffmanNode *huffmanTree, int n);
void selectMin(HuffmanNode *huffmanTree, int n, int *s1, int *s2);
void calcWPL(HuffmanNode *huffmanTree, int n, int *wpl);

int main()
{
    HuffmanNode huffmanTree[MAX];
    int n, wpl;
    printf("请输入叶子结点的个数：");
    scanf("%d", &n);
    createHuffmanTree(huffmanTree, n);
    calcWPL(huffmanTree, n, &wpl);
    printf("哈夫曼树的带权路径长度为：%d\n", wpl);
    return 0;
}

void createHuffmanTree(HuffmanNode *huffmanTree, int n){
    int i, s1, s2;
    // 初始化哈夫曼树，将所有节点的父节点，左右孩子都赋为-1
    for(i=0; i<2*n-1; i++){
        huffmanTree[i].data = i;
        huffmanTree[i].weight = 0;
        huffmanTree[i].parent = -1;
        huffmanTree[i].leftChild = -1;
        huffmanTree[i].rightChild = -1;
    }
    // 输入n个叶子节点的权值
    printf("请输入%d个叶子节点的权值：\n", n);
    for(i=0; i<n; i++){
        huffmanTree[i].weight = rand()%10+1;  // 这里用随机数生成权值
    }
    // 构建哈夫曼树
    for(i=n; i<2*n-1; i++){
        selectMin(huffmanTree, i, &s1, &s2);
        huffmanTree[s1].parent = i;
        huffmanTree[s2].parent = i;
        huffmanTree[i].leftChild = s1;
        huffmanTree[i].rightChild = s2;
        huffmanTree[i].weight = huffmanTree[s1].weight + huffmanTree[s2].weight;
    }
}

void selectMin(HuffmanNode *huffmanTree, int n, int *s1, int *s2){
    int i, min1, min2;
    min1 = min2 = 99999;
    for(i=0; i<n; i++){
        if(huffmanTree[i].parent == -1){
            if(huffmanTree[i].weight < min1){
                min2 = min1;
                *s2 = *s1;
                min1 = huffmanTree[i].weight;
                *s1 = i;
            }else if(huffmanTree[i].weight < min2){
                min2 = huffmanTree[i].weight;
                *s2 = i;
            }
        }
    }
}

void calcWPL(HuffmanNode *huffmanTree, int n, int *wpl){
    int i, root;
    *wpl = 0;
    // 找到根节点的位置
    for(i=0; i<2*n-1; i++){
        if(huffmanTree[i].parent == -1){
            root = i;
            break;
        }
    }
    // 计算带权路径长度
    for(i=0; i<n; i++){
        int cur = i;
        int w = 0;
        while(cur != root){
            if(huffmanTree[huffmanTree[cur].parent].leftChild == cur){
                w++;
            }
            cur = huffmanTree[cur].parent;
        }
        *wpl += w * huffmanTree[i].weight;
    }
}

这个算法中，首先构建哈夫曼树，然后通过遍历每一个叶子节点，计算出从该节点到根节点的路径长度，最终将所有路径长度累加起来，就是哈夫曼树的带权路径长度（WPL）。