On Tue, Sep 16, 2008 at 05:27:03AM +0900, Li Chen wrote:
> Hi all,
> 
> Just wonder:
> 
> 1)When substracting array2 from array1 to get the difference elements
> between two arrays(array1-array2), must array1.size >= array2?

irb is great for this stuff.

>> [1, 2] - [1, 3, 4]
=> [2]

> 2)Is there mentod in Array class that can  return the element only
> unique to either of two arrays?

http://ruby-doc.org/core/classes/Array.html

> For example, array1=[1,2,3],array2=[1,4,7]
> the return array is [2,3,4,7]


There might be a better way, but I came up with:

>> ([1, 2, 3] - [1, 4, 7]) + ([1, 4, 7] - [1, 2, 3])
=> [2, 3, 4, 7]

-- 
nathan
nathan_at_nathanpowell_dot_org

What kind of crazy nut would spend two or three hours a day just running?
		 ~ Steve Prefontaine
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