public TValue GetValue(TKey key) => _values[ArrayManager <TKey> .Get(ref _keys, key)];
 public TKey GetKey(TValue value) => _keys[ArrayManager <TValue> .Get(ref _values, value)];
        private void IncreaseArraySize()
        {
            ArrayManager <TKey> .IncreaseSize(ref _keys);

            ArrayManager <TValue> .IncreaseSize(ref _values);
        }