对于平面内给定的所有的水平或竖直线段，求其交点总数。运用线段树使程序在交点较少时能快于暴力算法-For a given plane, horizontal or vertical line of all, find the intersection number。

线段求交，使用二叉树保存消息树，状态树，还有已经求过交点的树，效率还行。-Line segment intersection, save the message using the binary tree, state tree, as well as the intersection of the tree has been seeking, efficiency, okay.