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ced on Dec 12, 2010 | parent | context | favorite | on: On C Linked Lists (Profiling and Optimizing)

But isn't that true if the list has one element? Then A->A, thus prev==next, but the list still isn't empty.

And if the head lives outside of the list proper, then you would need special-case code to handle deletion of the first element in the list (since the head contains a pointer to it). It wouldn't be branchless.

tedunangst on Dec 12, 2010 [–]

There is a fake element that is the head. It doesn't count as part of the list, but it's always in the list. With one element, the list is

    H->next = A, A->next = H
    H->prev = A, A->prev = H

ced on Dec 12, 2010 | [–]

Oh, that's a clever solution. Thanks.

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