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L2.R0.xor-1

Xor one byte · ○ open

Challenge

ladder rank

#25 (level L2)

family / transform

Transform / XorMask

cases

1 case(s), 1 output byte(s)

limits

program ≤ 256 bytes, ≤ 2048 steps/case

purpose

Apply the v0 xor-mask transform to the first byte.

Notes

The open frontier: output = input XOR 0x51 for any byte, 256-byte cap.

Unsolved. The input byte is hash-derived per seed, so the program must handle all 256 values; constant output fails. Known obstructions: the dispatch J = crazy(crazy(x,t1),t2) is non-injective and bounded below 243, so 256 private code paths cannot exist; identity dispatch needs operand byte 121, which no reachable operand cell in a fixed prefix accepts; dense landings force shared tails whose pointer cells sit in executed, byte-forced territory. Best coverage at this cap: 20/256.

Attempt it

git clone https://github.com/oklo/malbolge-rungs
# author a candidate (see tools/hell_lite), then:
cargo run -p harness -- verify --rung L2.R0.xor-1 --program your-candidate.mal --verbose