Given a polygon $P$ in the plane that can be translated, rotated and enlarged arbitrarily inside a unit square, the goal is to find a set of lines such that at least one of them always hits $P$ and the number of lines is minimized. We prove the solution is always a regular grid or a set of equidistant parallel lines, whose distance depends on $P$.

中文翻译：

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用最小网钓多角鱼

给定平面上的多边形 $P$，它可以在单位正方形内任意平移、旋转和放大，目标是找到一组线，使得其中至少有一条总是碰到 $P$，并且线的数量是最小化。我们证明解决方案总是规则网格或一组等距平行线，其距离取决于 $P$。