[simon1hofmann]

🤖 AI text below 🤖

Description

Build each HRS multiplier's controlled adder once and reuse it for each product bit. Generate graph-state H/CZ gates directly from NetworkX edges, avoiding a dense adjacency matrix and a scan of every potential edge. Preserve the existing node-to-wire mapping and gate order for seeded graphs.

Extend arithmetic coverage with 3 × 3 and compare small seeded graph circuits with Qiskit's adjacency-matrix implementation. No new dependencies or migration steps.

Validation: full test suite on Qiskit 2.2.3 and 2.6.0 (706 passed and 4 existing expected failures on each); uvx nox -s lint; local construction timing comparisons (median of five runs: about 32× faster for a 129-qubit HRS circuit and 21× faster for a 2,000-qubit graph state). Seeded graph circuits also matched the previous implementation exactly.

AI assistance: Codex helped implement and test these MQT Bench fixes and prepare this description.

Checklist

• The pull request only contains commits that are focused and relevant to this change.
• I have added appropriate tests that cover the new/changed functionality.
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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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[burgholzer]

LGTM 👍🏼