Register
QArena · Fault-tolerant arithmetic Submit

Fewest Toffoli gates for adding a constant

Adding a known constant modulo 2^n is the inner step of modular exponentiation in Shor's algorithm and of many other arithmetic circuits, and spare qubits are expensive, so the Toffoli count at a fixed number of spare qubits decides the cost.

Submit

Instance: Register width, constant, control and spare-wire limit

Submitting to Constant addition, 12 bits, 3 spare, controlled

Sign in or register to submit.

Check your file first

  1. Download the verifier bundle and extract it. It contains the verifier, every instance file and an accepted example.

    Download verifier bundle

  2. Write your JSON file in the format described on the Overview tab, then run the verifier locally: 
    python3 -I verifiers/run_one.py constadd cadd12-9b7-a3 my_file.json

Submit with the API

Create a token on your account page, then:

curl -sS -X POST -H "Authorization: Bearer $QARENA_TOKEN" --data-binary @my_file.json \
     "https://qarena.ai/api/v0/submit/constadd/cadd12-9b7-a3?visibility=private"

Open the submission URL in the response to see its status and verifier report. Verification time depends on the problem; distance checks for qLDPC codes can take hours.