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comparing arrays

If I have two arrays, what is a good paradigm for comparing what is in
them, to determine what elements they share, or don't share?

Specifically, each array could potentially contain the integers 1 to
9, but probably not all 9 integers.

MyArray1 = 1,2,3,5,6,7,8
MyArray2 = 1,4,6,7

I would need the answers to be arrays too:
MyArrayShared: 1,6,7
MyArrayNotShare d: 9

TIA
Jan 18 '06 #1
1 2249
On Wed, 18 Jan 2006 10:16:32 GMT, Donald Grove
<do*********@ve rizon.net> wrote:

You could go brute-force since these are such small arrays. Just
iterate over the one, and for each element iterate over the second.

If you needed maximum speed then your algorithm should use all
additional information that is available, for example:
* the arrays are sorted
* the length of an array can be calculated very quickly
* MyArray1 is longer than MyArray2.
There may be other operational characteristics that you can leverage.

-Tom.

If I have two arrays, what is a good paradigm for comparing what is in
them, to determine what elements they share, or don't share?

Specifically , each array could potentially contain the integers 1 to
9, but probably not all 9 integers.

MyArray1 = 1,2,3,5,6,7,8
MyArray2 = 1,4,6,7

I would need the answers to be arrays too:
MyArrayShare d: 1,6,7
MyArrayNotShar ed: 9

TIA


Jan 18 '06 #2

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