[ynfnehf]

You don't actually need two arrays to implement your idea. Since the combined size will be constant, just one array with an index indicating the split is enough.

When moving cards from one side to the other a lot of elements will have to be moved around. But for small n it should be much faster than using linked lists. And also relatively easy to implement in C.

The shifting of elements when inserting can be avoided by only swapping two positions. (ABXDEFC instead of ABXCDEF, when inserting X into ABCDEF). But by then you have just reinvented Fisher-Yates.

So the swapping in some of these algoritms is basically an implementation of your idea.