Echo two bytes · multiple cases

L1.R3.echo-2-multicase

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: #6 (historical identifier L1)
family / transform: EchoPrefix / Identity
cases: 2 cases, 2 output bytes each
limits: program ≤ 256 bytes, ≤ 1024 steps/case
task summary: The same echo program must pass additional cases.
exact contract: Registry JSON · L1.R3.echo-2-multicase

Harness documentation

Winning program

solutions/echo/echo-2.mal · 5 bytes · sha256 385b4edf9e49a9cd015866887b79f5c18c82ba9d7b6ff6ae3ab899cd3433d9c7

ubs`M

Solver

name: HeLL-Lite (tool)
type: tool
harness: tools/hell_lite compile-linear (deterministic straight-line template)
metric: 2/2 cases, 5 seeds
attribution notes: First-use opcode encoding of the straight-line IN/OUT sequence; each address has exactly one printable byte per opcode.

Task notes

The same echo program must pass additional cases.

Earlier record notes

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

Same 5-byte echo-2 program; fresh VM per case.

Verification transcript (native VM, 3 epochs)

epoch 0 · seed 7d8538fb4463… · 2/2 cases

case	input	expected	observed	status
0	50a6609629b1b250…	50a6	50a6	ok
1	766d51de1d2c1034…	766d	766d	ok

epoch 1 · seed 93f1254abe6b… · 2/2 cases

case	input	expected	observed	status
0	e4afca94b7491a8a…	e4af	e4af	ok
1	5ac33f732ef928fb…	5ac3	5ac3	ok

epoch 2 · seed de29f85f21f9… · 2/2 cases

case	input	expected	observed	status
0	cfa9879625b539d2…	cfa9	cfa9	ok
1	c4a0ce9418e4450c…	c4a0	c4a0	ok

Reproduce

git clone https://github.com/oklo/malbolge-rungs
cargo run -p harness -- verify --rung L1.R3.echo-2-multicase --program solutions/echo/echo-2.mal --epochs 3 --verbose