There is a 50-50 chance that the computer will either triple the amount you send to P2, or turn it to 0.
Whatever amount P2 receives, P2 will then decide how much of it to send back to you.
P2 also knows about this 50-50 chance of the computer turning the investment into 0.If P2 receives 0,
P2 will not know whether the computer turned your investment into 0, or whether you sent 0 to P2.
If P2 receives some positive amount, P2 will know that you sent one third of this amount and that
the computer tripled the amount you sent.