Human Resource Machine/Year 4

Strategy
This year, to go along with COPY FROM, you get a new instruction: COPYTO The IN conveyor is working again. Now they want you to take a pair of items off the IN conveyor, and place them on the OUT conveyor in reverse order. So if the first two items on the IN conveyor are 4, and then 5, they want you to place the 5 down on the OUT conveyor first, followed by the 4.
 * COPYTO: This instruction is always accompanied by a number. The instruction tells the worker to walk over to the box on the floor labeled with the specified number, and place a copy of the value in his/her hands into that box.  Note that you cannot instruct the worker to COPYTO a box if he/she is not holding anything.

In order to do this, you're going to need to take advantage of the space on the floor. There are three empty boxes for you to use. You can place something in them for temporary storage, and retrieve them later on. Remember that the worker's limitation is that he cannot hold more than one item at a time. So he needs to store the first item he picks up from the IN conveyor somewhere so that he can pick it back up after he's dropped the second item off on the OUT conveyor. Box 0 is just as good as any.

a:   INBOX COPYTO  0 INBOX OUTBOX COPYFROM 0 OUTBOX JUMP    a

Optimizing
It is not possible to further optimize this solution.

Performance
Steps    Size      Speed Goal       7         21 Reached    7         21