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Beginner Hint 1: Challenge Overview (AI-translated)

\n\n- The distributed files are a .NET application written in C# and a [flag checker](https://alpacahack.com/tags/flag-checker) that determines whether the entered string is the correct flag.\n- `AlpacaForm.exe` is the executable file used to launch the app on Windows. The C# code containing the actual validation logic is in `AlpacaForm.dll`.\n- `.dll` stands for Dynamic Link Library. In general, it is a file that contains code or data loaded and used by executable files or other programs.\n

\n\n

Beginner Hint 2: Reverse Engineering (AI-translated)

\n\n- `AlpacaForm.dll` can be decompiled and read in a form close to C# using a .NET decompiler such as ILSpy.\n- For example, try running `ilspycmd AlpacaForm.dll` to decompile it ([Ref](https://github.com/icsharpcode/ILSpy/tree/98ee6c3b8410e495b2fbbe9ca414090a962202c8/ICSharpCode.ILSpyCmd)).\n- After decompiling it, look for the function that validates the entered string.\n

\n","descriptionJa","\"この問題はLinux環境だけでも解けます。\"\n\n

初心者向けヒント1: 問題概要

\n\n- 配布ファイルは、C# で作られた .NET アプリケーションで、入力された文字列が正しいフラグかどうかを判定する[フラグチェッカー](https://alpacahack.com/tags/flag-checker)です。\n- `AlpacaForm.exe` は Windows でアプリを起動するための実行ファイルです。実際の判定処理を含む C# のコードは、`AlpacaForm.dll` に含まれています。\n- `.dll` は Dynamic Link Library の略で、一般には実行ファイルなどから読み込まれて使われるコードやデータを含むファイルです。\n

\n\n

初心者向けヒント2: リバースエンジニアリングの方法

\n\n- `AlpacaForm.dll` は ILSpy などの .NET デコンパイラで、C# に近い形へデコンパイルして読めます。\n- 例えば `ilspycmd AlpacaForm.dll` を実行してデコンパイルしてみましょう（[参考](https://github.com/icsharpcode/ILSpy/tree/98ee6c3b8410e495b2fbbe9ca414090a962202c8/ICSharpCode.ILSpyCmd)）。\n- デコンパイルしたら、入力された文字列を検証している関数を探してみましょう。\n

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