C# test if number exists in array and if not put it in

[realJSOP]

You cannot add to an array. You're going to have to use a list. If you don't know the difference between an array and a list, use google.

.45 ACP - because shooting twice is just silly
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"Why don't you tie a kerosene-soaked rag around your ankles so the ants won't climb up and eat your candy ass..." - Dale Earnhardt, 1997
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"The staggering layers of obscenity in your statement make it a work of art on so many levels." - J. Jystad, 2001

[Alex Manolescu]

John Simmons / outlaw programmer is right! If you know the number of elements in you're array, you can create an array of dimension = elements x 2 (for the duplicates). If you don't know the number of elements then you need to use another data structure, for example: a linked list! :) Cheer's, Alex Manolescu.

[Jimmanuel]

Wheels012 wrote:

Array.BinarySearch(numbers, 0, numbers.Length, intRnd);

It looks like you're just throwing random numbers (trying to, anyway) onto the end of the array, so how is this supposed to work if numbers is unsorted? Like others have said, use a List and when adding to it insert items at their proper index to keep it sorted, or use a hash table. :badger:

[PIEBALDconsult]

Luc Pattyn wrote:

HashSet

That's what I was going to suggest as well.

[petercrab]

I would definitely use a List(dynamic array) for what you want.

    List<int> numbers = new List<int>();

    private bool RndDuplicate(int intRnd)
    {
        if (numbers.Contains(intRnd))
            return true;
        else
        {
            numbers.Add(intRnd);
            return false;
        }
    }

[realJSOP]

Alex Manolescu wrote:

you can create an array of dimension = elements x 2 (for the duplicates).

But you would only do that if you're a retard, or completely new at programming.

Alex Manolescu wrote:

If you don't know the number of elements then you need to use another data structure, for example: a linked list!

Just use a List object. It lets you add/remove items, and even sort them. Jeeze!

.45 ACP - because shooting twice is just silly
-----
"Why don't you tie a kerosene-soaked rag around your ankles so the ants won't climb up and eat your candy ass..." - Dale Earnhardt, 1997
-----
"The staggering layers of obscenity in your statement make it a work of art on so many levels." - J. Jystad, 2001

[Luc Pattyn]

way too much code, and too slow for large sets.

HashSet set=new HashSet();

private bool RndDuplicate(int intRnd) {return !set.Add(intRnd);}

:)

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles]

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Merry Christmas and a Happy New Year to all.

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[Alex Manolescu]

John Simmons / outlaw programmer wrote:

Jeeze!

I've just replay my opinion. I've taught I could help to understand better the idea. No need to involve Jesus here! Cheer's, Alex Manolescu.

[Alex Manolescu]

Wow :) nice one! Thanks!

[Wheels012]

Thank you petercrab. That is just what I am looking for. Happy New Year, WHEELS