为了测试某种药物对小白鼠方向感的影响，生物学家在实验室做了一个矩形迷宫，入口和出口都确定为唯一的，且分布在矩形的不同边上。现在让你算出小白鼠最短需要走多少步，才可以从入口走到出口。-In order to test the impact of a drug on mice sense of direction, a biologist at the lab made a rectangular maze, inlet and outlet are determined to be unique and distributed in different sides of the rectangle. Now let you figure out how many steps need to take the shortest mice before they can go to the outlet　the inlet.