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Beginner Hint

\n\n- The flag is stored in `/flag-.txt`. Your goal is to read it.\n- Lean is a theorem prover, but it is also a functional programming language. In particular, Lean 4 has stronger support for general-purpose programming.\n- Try researching how to execute OS commands in Lean.\n\n

\n","descriptionJa","流行りの Lean を簡単に遊べる Web サービスを作りました。 \n証明を検証するだけだから、サーバーに悪さなんてできないよね？\n\n

初心者向けヒント

\n\n- フラグは `/flag-.txt` に保存されています。これを読み取るのがゴールです。\n- Lean は定理証明支援系であると同時に、関数型プログラミング言語でもあります。特に Lean 4 では、汎用プログラミングの側面が強化されています。\n- Lean でどう OS コマンドを実行できるかを調査してみましょう。\n\n

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