用C++完成输入n个叶子结点的权值构造哈夫曼树；根据哈夫曼树构造哈夫曼编码，并对密文完成解码工作

好的，以下是用C++实现输入n个叶子节点的权值构造哈夫曼树，并根据哈夫曼树构造哈夫曼编码，最后对密文进行解码的代码：

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

// 哈夫曼树节点
struct HuffmanNode {
    int val; // 权值
    char ch; // 叶子节点的字符
    HuffmanNode *left, *right; // 左右子节点
    HuffmanNode(int val, char ch = '\0', HuffmanNode *left = nullptr, HuffmanNode *right = nullptr) :
        val(val), ch(ch), left(left), right(right) {}
};

// 哈夫曼编码表
unordered_map<char, string> huffmanCode;

// 构造哈夫曼树
HuffmanNode* buildHuffmanTree(vector<int>& weights) {
    auto cmp = [](HuffmanNode* a, HuffmanNode* b) {
        return a->val > b->val;
    };
    priority_queue<HuffmanNode*, vector<HuffmanNode*>, decltype(cmp)> pq(cmp);
    for (int i = 0; i < weights.size(); ++i) {
        pq.push(new HuffmanNode(weights[i], (char)('A' + i)));
    }
    while (pq.size() > 1) {
        auto left = pq.top(); pq.pop();
        auto right = pq.top(); pq.pop();
        auto parent = new HuffmanNode(left->val + right->val, '\0', left, right);
        pq.push(parent);
    }
    return pq.top();
}

// 构造哈夫曼编码
void buildHuffmanCode(HuffmanNode* root, string code) {
    if (!root) return;
    if (root->ch != '\0') {
        huffmanCode[root->ch] = code;
    }
    buildHuffmanCode(root->left, code + '0');
    buildHuffmanCode(root->right, code + '1');
}

// 压缩数据
string compress(string data) {
    string compressed;
    for (char ch : data) {
        compressed += huffmanCode[ch];
    }
    return compressed;
}

// 解压缩数据
string decompress(string compressed, HuffmanNode* root) {
    string decompressed;
    auto curr = root;
    for (char ch : compressed) {
        if (ch == '0') {
            curr = curr->left;
        } else {
            curr = curr->right;
        }
        if (curr->ch != '\0') {
            decompressed += curr->ch;
            curr = root;
        }
    }
    return decompressed;
}

int main() {
    int n;
    cout << "请输入叶子节点的个数n：" << endl;
    cin >> n;
    vector<int> weights(n);
    cout << "请输入n个叶子节点的权值：" << endl;
    for (int i = 0; i < n; ++i) {
        cin >> weights[i];
    }
    HuffmanNode* root = buildHuffmanTree(weights);
    buildHuffmanCode(root, "");
    string data;
    cout << "请输入需要压缩的数据：" << endl;
    cin >> data;
    string compressed = compress(data);
    cout << "压缩后的数据：" << compressed << endl;
    string decompressed = decompress(compressed, root);
    cout << "解压缩后的数据：" << decompressed << endl;
    return 0;
}

注意，此代码中将输入的叶子节点的字符默认为'A'到'A'+n-1，如果需要输入其他字符，可以修改代码。另外，此代码中没有对输入数据进行错误处理，如果输入数据不符合要求，程序可能会出错。