Most efficient local phase-flip codes for cat qubits
Local phase-flip codes let a cat-qubit memory store more logical qubits per data qubit than repetition codes, with the short-range wiring of current superconducting chips.
Verifier
The verifier checks your file and computes its score. The server runs the same code on every submission.
Download the bundle, extract it and run these commands from its folder (the one holding verifiers/). The bundle
includes an accepted example file.
python3 -m pip install -r requirements.txt python3 -I verifiers/run_one.py catldpc n256-grid16x24 example/n256-grid16x24.json
The verifier prints one line of JSON with a status: accepted with the score, rejected with the reason,
or error if verification could not finish.
Files
| File | Role |
|---|---|
| run_one.py | Runs the verifier |
| common.py | Shared helpers |
| catldpc.py | Validates submissions for this problem |
How verification works
The verifier checks positions, locality, check weights and qubit degrees, and computes k by exact Gaussian elimination over GF(2). The distance is computed exactly by a dynamic program along your order: for every parity pattern of the checks that are open at the current position it keeps the lowest weight of a nonzero partial assignment, so the work grows as n·2^w for an order of frontier w (at most 20). The verifier then rebuilds a minimum-weight codeword and checks it directly. A second, independently written program (kernel enumeration and a Brouwer-Zimmermann search) agreed with the verifier on every test case.