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    <p>I see your point, that you'd like to avoid doing two passes over your source container. Unfortunately, I don't believe there's a standard algorithm that will do this. It would be possible to create your own algorithm that would copy elements to a new container and remove from the source container (in the same sense as remove_if; you'd have to do an erase afterward) in one pass. Your container size and performance requirements would dictate whether the effort of creating such an algorithm would be better than making two passes.</p> <p>Edit: I came up with a quick implementation:</p> <pre><code>template&lt;typename F_ITER, typename O_ITER, typename FTOR&gt; F_ITER move_if(F_ITER begin, F_ITER end, O_ITER dest, FTOR match) { F_ITER result = begin; for(; begin != end; ++begin) { if (match(*begin)) { *dest++ = *begin; } else { *result++ = *begin; } } return result; } </code></pre> <p>Edit: Maybe there is confusion in what is meant by a "pass". In the OP's solution, there is a call to remove_copy_if() and a call to remove_if(). Each of these will traverse the entirety of the original container. Then there is a call to erase(). This will traverse any elements that were removed from the original container.</p> <p>If my algorithm is used to copy the removed elements to a new container (using begin() the original container for the output iterator will not work, as dirkgently demonstrated), it will perform one pass, copying the removed elements to the new container by means of a back_inserter or some such mechanism. An erase will still be required, just as with remove_if(). One pass over the original container is eliminated, which I believe is what the OP was after.</p>
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    1. PONow to remove elements that match a predicate?
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    1. USFred Larson
    1. USFred Larson
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    1. COFinally, someone paid enough attention to answer the question the OP is really asking! I'd upvote this five times if it were allowed.
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    2. CO@dirkgently, I don't see where the OP asked for an in-place splice. He wants to remove certain elements from one container and put them into another. This algorithm works fine for that, as far as I know from the admittedly limited testing I did. Using this algorithm in-place makes no sense.
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    3. CO@Fred: Splice is splitting up a list. I generalized. That's what the OP wants: A list where each element satifies a given predicate and his problem is "how far back from the end of the source container to erase" i.e. removal.
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