Problem 60603. ICFP2024 003: Lambdaman 5

Richard Zapor

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The ICFP2024 contest was held June 29 thru July 1. The contest consisted of five parts: ICFP Language, Lambdaman maze, Starship flying, 3D - graph programming, and  Efficiency - processing complex ICFP message to a numerical value.
The ICFP Language is based on Lambda Calculus.
The Lambdaman 5 maze is a 11x16 matrix L near middle. Points are '#' wall and '.' a cheese bit. Wall=0,L=1,Cheese=2 
The contest goal was to write a minimal size, bytes, expression that moves L, Lambdaman, to eat each cheese bit.
Lambdaman 5 was given as an ICFP encrypted text String: Slllllaaaaaaaalll~llllalllllllllll~lllallaaaaaallll~llallallllllalll~lallalllaalllall~lallallaFlalllal~lalllallllalllal~llalllaaaalllall~lllallllllllalll~llllaaaaaaaallll~llllllllllllllll~
.....########...
....#...........
...#..######....
..#..#......#...
.#..#...##...#..
.#..#..#L.#...#.
.#...#....#...#.
..#...####...#..
...#........#...
....########....
................
The contest's best Lambdaman5 solution was written in ICFP to reduce length versus ~150 U/R/D/L commands.
B$ L" B. S3/,6%},!-"$!-!.Z} B$ v" B$ v" B$ v" SFOOLL>>LL>FO>>>FFL>>>FFFFOFOFFOLLLLOFOLO L! B. B. v! v! v! which defines the function L" as triple(x) from B$ L" and L! B. B. v! v! v!  The usage B$ v" invokes triple(x) thus the main becomes triple(triple(triple(SFOOLL>>LL>FO>>>FFL>>>FFFFOFOFFOLLLLOFOLO) )) or 27 repeats of the string.
The big hint here is that ICFP O is U, > is D, F is L, and L is R when decrypted. Running into walls causes no movement and since this is a spiral maze there appears to be a short sequence that spans all the cheesy bits when repeated.  To me it was nuts that someone devised this short sequence.
This challenge is to return a string of commands [UDLR] with minimal matlab program size that eats all the cheese bits.
I will be posting the entire ICFP2024 contest challenges and best solutions.