※ 引述《Leon (Achilles)》之铭言：
: : 接着说明一下直线截成线段的问题。
: : 对偶的时候，点(a,b)对偶成直线y=ax+b。
: : 考虑两个直线的交点，也就是两条直线解联立方程式。
: : 根据公式解，交点的座标范围一定会在 |a|*|b|+|c|*|d| 之内。
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: First, I don't understant your notation.
: What do you mean by the range |a|*|b|+|c|*|d| ?
:
: It seems not a range in 2D ?
:
:
: And I have the same question for you.
:
: Assume you have N lines, based on your description
: You claim there is a range for the intersection.
:
: Then, how many operations you need to calculate the range?
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:
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恩 你说的没错 那么范围最大到 |d|+|b| 才对

you are wrong again, look, there is (a-c) term!

恩 你说的没错　除非abcd都是整数　范围才是 |d|+|b|

then revise your post. Everyone should be responsible towhat they write

这是当然 XD

OK, your first statement is wrong. Now you can answerthe second question: