std :: unordered_set 是连续的吗？

确切该标准并未详细介绍容器的实现... 但是该标准确实规定了一些限制实际表示的行为。

The exact implementation of containers is not detailed by the standard... however the standard does prescribes a number of behaviors which constrains the actual representation.

例如， std :: unordered_set 必须是内存稳定的：对元素的引用/地址即使在添加/删除 other 元素时也有效

For example, std::unordered_set is required to be memory stable: a reference to/address of an element is valid even when adding/removing other elements.

实现此目标的唯一方法是或多或少地独立分配元素。使用连续的内存分配无法实现此目的，因为这样的分配必然会受到限制，因此可能会变得过于庞大，无法在更大的块中重新分配元素。

The only way to achieve this is by allocating elements more or less independently. It cannot be achieved with a contiguous memory allocation as such an allocation would necessarily be bounded, and thus could be overgrown with no possibility of re-allocating the elements in a bigger chunk.