Find the Special Node

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**This is an interactive task** There is a tree consisting of $N$ nodes. A certain node $X$ is marked as special, but you don't know $X$ - your task is to find it. To achieve this, you can ask queries to obtain information about $X$. To be specific, you can ask queries in the form: `? Y` where $1 \le Y \le N$, and you will be provided with a random node on the path from node $Y$ to node $X$,

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solution.cppC++17

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