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Thread: Storing unique random numbers

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    Default Storing unique random numbers

    Im trying to store random id's in my code , but im trying to figure out how to store only unique id's how would i do that ?

    public void storeCustomer (Customer newCustomer)
    {
    if(newCustomer.getCustomerID().equals("unknown"))
    {
    newCustomer.generatorCustomerID("ab-",6);

    customerMap.put(newCustomer.getCustomerID(),newCus tomer);
    }
    else
    {
    customerMap.put(newCustomer.getCustomerID(),newCus tomer);
    }
    }


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    Default Re: Storing unique random numbers

    How would you do this without a computer? Say you have a 100-sided die. You want to generate a list of 10 unique random numbers. What do you do?

    Write out instructions that you could hand to a stranger to have them accomplish the goal, and when you have that, you'll have an algorithm that you can implement.

    --- Update ---

    Nevermind, crossposted.

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    http://www.java-forums.org/new-java/71377-storing-unique-random-numbers.html

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    Default Re: Storing unique random numbers

    well u do a id by string followed by 6 random numbers then adds to the map . but how would u just add n not use it again

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    Default Re: Storing unique random numbers

    I wouldn't use a Map. But since I don't know what help you've already received, I'm not going to waste my time repeating what you might have already heard.

    This is why we ask people not to crosspost, or to at least let us know when they do so.

    Good luck.
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