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Ever tried removing element from a middle of vector?

Yes, the world does not end. For small objects and `vector`s, it's probably quicker, because 1) you found it quicker due to cache locality and 2) there were no system calls to release memory.

So, what you say is: I don't care to implement an efficient solution, because the CPU cache will fix it anyway. That way of thinking is well known as "The Java way of problem solving" (TM)

That's not what he said, and his solution is not "inefficient." CPUs have no emotions; if it runs faster due to cache, it's simply the better solution.

For the use case required by ZeroMQ, it's faster in all cases, because swap-with-last and shrink is O(1). Sure, if CPUs didn't have caches, a list might be faster.

Do you see where this is going? The C way of solving problems consists of adding one more level of indirection (ever heard of 3-star C programmers?), because it becomes more efficient asymptotically that way. Nevermind the hidden factor of 100-1000 due to pipeline stalls and cache misses.

Fortunately not all C programmers think that way.

My solution is more efficient in the normal case, ignoring the asymptotic case that never happens.

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