Concussive Sequence

For a sequence $X$ of length $L \ (L \geq 3)$, we call $X$ a **concussive sequence** if and only if: - For all $i \ (1\lt i \lt L)$, $X_{i-1}\lt X_i \gt X_{i+1}$ or $X_{i-1}\gt X_i \lt X_{i+1}$ holds. You're given a sequence $A$ of length $N$. Your task is to rearrange $A$ to make it a **concussive sequence**. If multiple such rearrangements exist, print any. If no such rearrangement exists,