Suppose that in a Cartesian coordinate system on an infinite plane, the x-axis represents the ground and there are n rainscreens in the sky.Every rainscreen can be described as a segment which starts from the. ). Now if it starts to rain from the infinite high sky, I want you to tell me how many units of the x-axis will not get rained on.To simplify the problem,the rain can only move vertically whenever it falls.Note that two rainscreens can overlap and intersect with each other, and there is no rainscreen which is placed vertically.
Suppose that in a Cartesian coordinate system on an infinite plane, the x-axis represents the ground and there are n rainscreens (We don't consider their thickness.) in the sky. Every rainscreen can be described as a segment which starts from the (x_1, y_1) (x 1 ,y 1 ) and ends at (x_2, y_2) (x 2 ,y 2 ). Now if it starts to rain from the infinite high sky, I want you to tell me how many units of the x-axis will not get rained on. To simplify the problem,the rain can only move vertically whenever it falls. Note that two rainscreens can overlap and intersect with each other, and there is no rainscreen which is placed vertically.
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