1）对输入数据构造成一棵Huffman 树； 2）对生成Huffman 树进行Huffman 编码c++代码

1）构造Huffman树的代码：

#include <queue>
#include <vector>

struct Node {
    int weight;
    Node* left;
    Node* right;

    Node(int w, Node* l = nullptr, Node* r = nullptr) :
        weight(w), left(l), right(r) {}
};

struct cmp {
    bool operator()(const Node* lhs, const Node* rhs) const { return lhs->weight > rhs->weight; }
};

Node* constructHuffmanTree(const std::vector<int>& weights) {
    std::priority_queue<Node*, std::vector<Node*>, cmp> pq;
    for (auto w : weights) {
        pq.push(new Node(w));
    }
    while (pq.size() > 1) {
        auto left = pq.top();
        pq.pop();
        auto right = pq.top();
        pq.pop();
        auto parent = new Node(left->weight + right->weight, left, right);
        pq.push(parent);
    }
    return pq.top();
}

2）生成Huffman编码的代码：

#include <unordered_map>
#include <string>

void generateHuffmanCode(Node* root, const std::string& prefix, std::unordered_map<char, std::string>& codeMap) {
    if (!root) return;
    if (!root->left && !root->right) {
        codeMap.insert({ prefix[0], prefix.substr(1) });
        return;
    }
    generateHuffmanCode(root->left, prefix + "0", codeMap);
    generateHuffmanCode(root->right, prefix + "1", codeMap);
}

std::unordered_map<char, std::string> getHuffmanCode(Node* root) {
    std::unordered_map<char, std::string> codeMap;
    generateHuffmanCode(root, "", codeMap);
    return codeMap;
}

其中，`root`是Huffman树的根节点，`codeMap`是字符和对应编码的映射表。函数`generateHuffmanCode`递归地遍历Huffman树，对于每个叶子节点，记录下字符和对应的编码前缀，最终将映射表存入`codeMap`中。函数`getHuffmanCode`是对外暴露的接口，返回字符和对应编码的映射表。