Echo one byte

L1.R0.echo-1

Native verification status · ● solved

What this result establishes

Public example suite. Fixed public examples, with exact output and halt required. Canonical copying solutions may be more general than the tested suite; the suite alone does not establish that.

Placement: Verified canonical or tool baseline. Similar slots are retained for historical continuity. How rank is interpreted.

Challenge

ladder rank: #3 (historical identifier L1)
family / transform: EchoPrefix / Identity
cases: 1 case, 1 output byte each
limits: program ≤ 64 bytes, ≤ 32 steps/case
task summary: Copy one input byte and halt.
exact contract: Registry JSON · L1.R0.echo-1

Winning program

solutions/echo/echo-first-byte.mal · 3 bytes canonical (4 on disk) · sha256 canonical 681f8033410df7a4a5d7eaa3f8c730929459de77ed4fd27cac02cd813ab36c0c · file 7e06b0c66f3253e37e419ad8b59365950c5d484db497487c95a4bad6cc1bb2a7

ubO

Solver

name: ubO (canonical)
type: canonical
metric: 1/1 case, multiple seeds
attribution notes: Minimal 3-instruction classic-Malbolge program (IN, OUT, HALT); long predates this project.

Task notes

Copy one input byte and halt.

Earlier record notes

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

Read one byte, echo it, halt.

Verification transcript (native VM, 3 epochs)

epoch 0 · seed 3f25ad1e707d… · 1/1 cases

case	input	expected	observed	status
0	cbdc0d19c952cdc1…	cb	cb	ok

epoch 1 · seed 01a249d3dc41… · 1/1 cases

case	input	expected	observed	status
0	43e5aa288abdbafd…	43	43	ok

epoch 2 · seed a087391785a1… · 1/1 cases

case	input	expected	observed	status
0	8bc47fb6c43abdc3…	8b	8b	ok

Reproduce

git clone https://github.com/oklo/malbolge-rungs
cargo run -p harness -- verify --rung L1.R0.echo-1 --program solutions/echo/echo-first-byte.mal --epochs 3 --verbose