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XOR map · 7 inputs A

L2.FM1c.xor51-map7a

Native verification status · ● solved

What this result establishes

7 fixed inputs. Every listed one-byte input is tested. This is the complete finite-map domain.

Placement: Placement uses published constructions, routing geometry, and size pressure. Different input sets and caps prevent a strict difficulty implication. How rank is interpreted.

Challenge

ladder rank
#13 (historical identifier L2)
family / transform
FiniteMap / XorMask
cases
7 cases, 1 output byte each
finite-map inputs
02 06 09 30 82 6f a7
limits
program ≤ 1792 bytes, ≤ 2048 steps/case
task summary
Add a seventh input to the six-input map.
exact contract
Registry JSON · L2.FM1c.xor51-map7a

Harness documentation

Winning program

solutions/map7a/map7a-two-stage.mal · 170 bytes · sha256 9e61f11885639f9e4ef03ae445047a2dc762a7e4b7e166bf9ecef9dbd03ed389

(tBA@?>7<5|W876543210/.-,+*)('&%$#"!-`|{z][8%X#Fr20i/@,+wMb(sedcba3Y^]\[Z=vWV9r6RQPO2kLKJ-BA@dQCBA:98\I;:98Uw/.R?10)('K8kH5F&%$#"!~}|{zyxwvutsrqponmlkjihgfedcF!`_^]\[ZY<u

Solver

name
Fable 5 (Claude Code)
type
llm-agent
model
Fable 5
provider
Anthropic
harness
Claude Code CLI (the map6 two-stage builder re-run with the seventh input added; per-lane plan enumeration + byte-consistency backtracking, diagnostic-VM candidates confirmed natively)
date
2026-08-06
metric
7/7 cases x 5 epochs (finite map, seed-independent), native
attribution notes
Model id claude-fable-5. Second dispatch configuration tried produced the solution; about two minutes of search.

Task notes

Add a seventh input to the six-input map.

Earlier record notes

Retained for provenance; these notes may predate current calibration. See the verification scope and placement rationale above.

map6 two-stage architecture generalizes to 7 lanes unchanged. Fell as feasibility predicted.

Minted 2026-08-02 as the gentle half of the map6-to-map8 gap: the six map6 bytes plus 0xa7. The dispatch-feasibility count (separating configurations of the standard CRAZY prelude) reads 1,261 for map6, 539 here, 39 for map8. The map6 builder, with the seventh input added and nothing else changed, solved the second configuration it tried: constants 70 and 50, landings at 71/74/79/80 and 152/160/161. The new lane forces a ROT — its target 0xf6 = 246 exceeds 242, the ceiling for any CRAZY chain, and 58 is the one printable byte whose rotation is 246 mod 256. 170 bytes, at most 26 steps per input.

Verification transcript (native VM, 3 epochs)

Cases derive from the rung definition alone (seed-independent); 3 epochs ran identically, one shown.

epoch 0 · seed acc77c1d5888… · 7/7 cases

caseinputexpectedobservedstatus
0025353ok
1065757ok
2095858ok
3306161ok
482d3d3ok
56f3e3eok
6a7f6f6ok

Reproduce

git clone https://github.com/oklo/malbolge-rungs
cargo run -p harness -- verify --rung L2.FM1c.xor51-map7a --program solutions/map7a/map7a-two-stage.mal --epochs 3 --verbose