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This may be a question repeated many times, but I want to know your opinion.
I submitted a journal paper for an algorithm (Computer Science). Fearing that the review process take too long, I decided to submit a short-version conference paper, while the long version is under-review. I received the journal review comments, and re-sent the modifications to the journal. Meanwhile, the conference paper was accepted. But the camera-ready is not sent yet.
The problem is that both papers are about the same idea. There is also some copy-pasted parts in both papers. But:
1) the editor of the journal was not informed about the conference paper (I heard that I should tell the journal about any published papers - but note that the conference paper is not yet published - not even the camera ready is submitted),
2) the organization organizing the conference, is not the same that manage the journal. I have been told that there are conflicting copyrights.
The proposed solutions (that colleagues told me about):
a) submit both as is !
b) submit both (but with change in text).
c) do not submit the conference paper (but I heard this can be harmful)
d) tell the editor now (but honestly, the journal is way more important than the conference).