用C++代码求哈夫曼树WPL值

下面是一个使用C++语言实现求哈夫曼树WPL值的示例代码：

#include <iostream>
#include <queue>
using namespace std;

struct TreeNode {
    int val;
    TreeNode* left;
    TreeNode* right;
    TreeNode(int x) : val(x), left(NULL), right(NULL) {}
};

struct cmp {
    bool operator()(TreeNode* a, TreeNode* b) {
        return a->val > b->val;
    }
};

int getWPL(TreeNode* root, int depth) {
    if (root->left == NULL && root->right == NULL) {
        return root->val * depth;
    }
    int wpl = 0;
    if (root->left != NULL) {
        wpl += getWPL(root->left, depth + 1);
    }
    if (root->right != NULL) {
        wpl += getWPL(root->right, depth + 1);
    }
    return wpl;
}

int main() {
    int n;
    cin >> n;
    priority_queue<TreeNode*, vector<TreeNode*>, cmp> q;
    for (int i = 0; i < n; i++) {
        int val;
        cin >> val;
        TreeNode* node = new TreeNode(val);
        q.push(node);
    }
    while (q.size() > 1) {
        TreeNode* node1 = q.top();
        q.pop();
        TreeNode* node2 = q.top();
        q.pop();
        TreeNode* newNode = new TreeNode(node1->val + node2->val);
        newNode->left = node1;
        newNode->right = node2;
        q.push(newNode);
    }
    TreeNode* root = q.top();
    int wpl = getWPL(root, 0);
    cout << wpl << endl;
    return 0;
}

该代码首先读入叶子节点的数量和权值，然后使用优先队列来构建哈夫曼树。接着，定义一个递归函数`getWPL`来计算WPL值，函数参数中的`depth`表示当前节点到根节点的路径长度。最后，输出计算得到的WPL值即可。