C++ STL 库：unordered_map 与 unordered_set 底层剖析

1.unordered_map、unordered_set的基本结构

🚩unordered_set：

template <class K, class V>
class unordered_set {
    struct SetKeyOfT {
        const K& operator()(const K& key) {
            return key;
        }
    };
public:
    typedef typename hash_bucket::HashTable<K, K, SetKeyOfT>::const_iterator iterator;
    typedef typename hash_bucket::HashTable<K, K, SetKeyOfT>::const_iterator const_iterator;
    const_iterator begin() const {
        return _ht.begin();
    }
    const_iterator end() const {
        return _ht.end();
    }
    pair<const_iterator, bool> insert(const K& key) {
        pair<typename hash_bucket::HashTable<K, K, SetKeyOfT>::iterator, bool> ret = _ht.Insert(key);
        return pair<const_iterator, bool>(ret.first, ret.second);
    }
private:
    hash_bucket::HashTable<K, K, SetKeyOfT> _ht;
};