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Read three points (p1,p2 and p0) as ordered pairs (x,y) wilere p0 is the origin and find the orientation of p0p1 with p0p2. Print orientation based on the sign of the value of the expression (x1−x0)(y2−y0)−(x2−x0)(y1−y0). For example, if the three points are p0(0,0), p1(2,10) and p2(3,3), then the orientation of p0p1 with p0p2 is clockwise whereas, if the three points are p0 (0,0),p1(7,2) and p2(3,3), then the orientation of p0p1 with p0p2 is counterclockwise

User RalfFriedl
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Final answer:

The orientation of line segments from the origin to different points in a Cartesian coordinate system can be determined by a simple expression involving the coordinates of these points. A positive result indicates counterclockwise orientation, negative indicates clockwise, and zero indicates collinearity.

Step-by-step explanation:

The orientation of line segments from a fixed point, such as the origin (p0), to two other points (p1 and p2) can be found using the cross product of the vectors representing these line segments. In a two-dimensional Cartesian coordinate system, this cross product is simplified to a determinant-like expression which will indicate the orientation based on its sign.

Given points p0(0,0), p1(x1,y1), and p2(x2,y2), the expression (x1-x0)(y2-y0) - (x2-x0)(y1-y0) can determine the orientation of segment p0p1 with respect to p0p2. If the expression is positive, the orientation is counterclockwise; if negative, clockwise; and if zero, the points are collinear.

For p0(0,0), p1(2,10), and p2(3,3), the resulting expression (2-0)(3-0) - (3-0)(10-0) gives -27, which indicates a clockwise orientation. Conversely, for p0(0,0), p1(7,2), and p2(3,3), the expression (7-0)(3-0) - (3-0)(2-0) gives 15, indicating a counterclockwise orientation.

User ChristofferH
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