Magic Trick solutions

Magic Trick was solved using Racket by 5 contestants. Solution sizes: average 1784 bytes (shortest: 505; longest: 3922).

13504.

Nori (3922 B)
16086.

singingmatt (2224 B)
19593.

IMDagger (937 B)
19961.

cky (505 B)
25292.

Weshmek (1334 B)