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L2.C0.xor51-cov32

Xor-mask coverage over at least 32 of 256 inputs · ○ open

Challenge

ladder rank

#18 (level L2)

family / transform

CoverageTransform / XorMask

cases

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

pass threshold

≥ 32 of 256 correct

limits

program ≤ 4096 bytes, ≤ 2048 steps/case

purpose

Every block enumerates all 256 single-byte inputs; the candidate must halt with the correct xor51 output on at least 32 of them. Mismatches and non-halting runs on other inputs are tolerated. This makes partial-coverage progress a deterministic rung instead of a per-block lottery.

Notes

Partial-credit XOR: ≥32 of 256 bytes correct. Best known 27/256.

All 256 input bytes are enumerated; the rung passes at 32 correct. The best known program reaches 27: identity dispatch J(x)=x via crazy(crazy(x,121),121), a shared six-op station, per-lane pointer cells, 4096 bytes. The shared pointer pool runs out near 30 lanes.

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.C0.xor51-cov32 --program your-candidate.mal --verbose