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Not Prime Permutation

CodeChefRating 1447Open on judge ↗

You are given a permutation $P$ of the integers $\{1, 2, 3, \ldots N\}$. Find **any** permutation $A$ of $\{1, 2, \ldots, N\}$ such that, for *every* index $i$ ($1 \leq i \leq N$), $A_i + P_i$ is **not** a [prime number](https://en.wikipedia.org/wiki/Prime_number). If no such permutation $A$ exists, print $-1$ instead. **Note:** A permutation of $\{1, 2, \ldots, N\}$ is an array of length

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solution.cppC++17

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