#P4623. Triangles and Lines Intersection
Triangles and Lines Intersection
Triangles and Lines Intersection
Given \(N\) triangles and \(M\) lines, where each line is either horizontal (parallel to the \(x\)-axis) or vertical (parallel to the \(y\)-axis), determine for each line how many triangles it crosses.
A line is said to cross a triangle if and only if it splits the triangle into two parts with strictly positive areas. In other words, for a horizontal line \(y=c\), the line crosses a triangle if and only if the triangle has at least one vertex with \(y>c\) and at least one vertex with \(yc\) and one with \(x<c\).
inputFormat
The first line contains two integers \(N\) and \(M\). The next \(N\) lines each contain six integers \(x_1\, y_1\, x_2\, y_2\, x_3\, y_3\), representing the coordinates of the vertices of a triangle. The following \(M\) lines each contain a character and an integer. The character is either H
(for a horizontal line \(y=c\)) or V
(for a vertical line \(x=c\)).
outputFormat
Output \(M\) lines, where the \(i\)-th line contains a single integer indicating the number of triangles crossed by the corresponding line.
sample
2 2
0 0 2 0 1 3
0 1 2 1 1 -1
H 1
V 1
2
2
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