Here's one answer I got from randomly picking. Each toy is either bought or passed (no repeats). I got the exact answer by getting: yoyo, duckie to elephant (f

Here's one answer I got from randomly picking. Each toy is either bought or passed (no repeats). I got the exact answer by getting: yoyo, duckie to elephant (from left to right, then down), and checkers. I'm trying to see if it's possible to get a more general solution rather than trial / error