Now we will give you a graph, there are many points in the graph. We will choose two different points arbitrarily, and connect them as a line. Please tell us that whether these points (Include the two points referred above) is on the left side of the line, or lying on the line. or on the right side of the line. For example,
There are four points in the graph: A, B, C, D. we connect C and D. Now C and D form a new line “CD”. Obviously, C and D are lying on the line “CD”. A is on the right side of CD, and B is on the left side of CD. What’s more, A is on the left side of line DC, and B is on the right side of line DC. So line “CD” and “DC” are different in this problem;