# random subset made by random selection of different elements from a given set

Discussion in 'C' started by elshadai, Mar 14, 2010.

1. ### elshadaiNew Member

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Hey all,

My name is Elshadai,

I am just a beginner in C/C++. I want to write a code in C/C++ the can select randomly a subset of integers both different from a given set. To be more concrete I have the following situation:

A=[1,2,3,4,5,6,7,8,9,10],

I want to make a subset of 4 elements from A whose element are chosen from A randomly and those element must be different from each other. I need a sets like :

B=[1,7,4,9] or C=[2,10,7,1] or D=[10,3,5,6] ....

Is there any one can help me?

Thank you so much

2. ### xpi0t0sMentor

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Pick 4 random numbers. Check if any are equal. If they are, change one. Repeat until you have no more duplicates.

3. ### elshadaiNew Member

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Thank you for you idea,
the problem is how to do what u say in c/c++?

4. ### xpi0t0sMentor

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Do you know how to pick one random number?

5. ### virxenActive Member

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