Imagine you have an infinite 2D plane with Cartesian coordinate system. Initially, all the integral points are painted as white. You are given two integers n, and m. Please paint exactly n integral points to black such that there are exactly m pairs of points which satisfy the following conditions:
Imagine you have an infinite 2D plane with Cartesian coordinate system. Initially, all the integral points are painted as white. You are given two integers n, and m. Please paint exactly n integral points to black such that there are exactly m pairs of points which satisfy the following conditions: 1. The two points are colored by different colors. 2. the two points are adjacent. We call two integral points (x_1, y_1) (x 1 ,y 1 ) and (x_2, y_2) (x 2 ,y 2 ) being adjacent if and only if |x_1 - x_2| + |y_1 - y_2| = 1 ∣x 1 −x 2 ∣+∣y 1 −y 2 ∣=1. (|v| means the absolute value of v.) 3. The x and y coordinates of all black points are in the range [-10^9, 10^9] [−10 9 ,10 9 ].
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