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Beginner Hint 1

\n\n- Your goal is to recover the value of `FLAG` from the values written in `output.txt`.\n- The `bytes_to_long` function is provided by the `pycryptodome` package.\n- The same package also provides the inverse function, `long_to_bytes`. Once you have recovered `FLAG` as an integer, you can use this function to convert it back into the original string.\n\n

\n\n

Beginner Hint 2

\n\n- A well-known identity relating addition and bitwise operations is `A + B = (A xor B) + 2 * (A and B)`. A good starting point is to understand why this identity holds.\n\n

\n","descriptionJa","A+B を計算すればフラグがわかるよ! あれ、A と B っていくつだっけ…?\n\n

初心者向けヒント 1

\n\n- この問題の目標は `output.txt` に書かれた値から `FLAG` の値を求めることです。\n- `bytes_to_long` 関数は `pycryptodome` パッケージに含まれている関数です。\n- 同パッケージの `long_to_bytes` 関数がその逆を行う関数です。`FLAG` が求まったあとは、この関数を用いることで文字列に変換することができます。\n\n

\n\n

初心者向けヒント 2

\n\n- 足し算とビット演算の関係を表す有名な式として、`A + B = (A xor B) + 2 * (A and B)` があります。なぜこの式が成り立つのかを理解することから始めると良いでしょう。\n\n

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