There is a rectangular field with dimensions m $ imes$ n. The field has boundary horizontal fences at positions $1$ and m, and boundary vertical fences at positions $1$ and n.

Inside the field, additional horizontal fences are placed at positions specified by the array hFences, and additional vertical fences are placed at positions specified by the array vFences.

You can remove any number of horizontal or vertical fences, including zero. Return the maximum area of a square field that can be formed by the remaining fences, modulo $10^9 + 7$. If no square field can be formed, return $-1$.

Constraints:

• $3 \leq$ m, n $\leq 10^9$

• $1 \leq$ hFences.length, vFences.length $\leq 600$

• $1 <$ hFences[i] $<$ m

• $1 <$ vFences[i] $<$ n

• All elements in hFences and vFences are unique.

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