0001 struct HuffChar { //超字符
0002    char ch;  uint32_t weight; //字符、频数
0003    HuffChar(uint32_t w = 0, char c = '^') : weight(w), ch(c) {}; //构造
0004    HuffChar(const HuffChar& hc) : weight(hc.weight), ch(hc.ch) {}; //复制
0005    bool operator<(const HuffChar& hc) { return weight > hc.weight; } //比较器：故意大小颠倒
0006 }; //HuffChar