Designing an arbitrary random class

Question

I know that C # has a Random class and possibly several classes in LINQ, but if I were to write my own code to randomly select an item from a collection without using any built-in .NET objects, how can I do this?

I can’t cover up the logic required for this - how would I tell the system when to stop the iteration and select the current value - at random?

EDIT: This is a hypothetical question. This is not related to production coding. I'm just curious.

thanks

Answer 1

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Answer 2

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Random r = new Random();
int randomIndex = r.Next(0, myCollection.Size -1);
var randomCollectionItem = myCollection[randomIndex];

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Answer 3

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Answer 4

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rnd = seed; // some starting value 
rnd = (a * rnd + b)  % c;  // next value
...

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Answer 5

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int index = customRandomGenerator.Next();
var selection = items[index];

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int index = customRandomGenerator.Next();
Item selection = null;
for (int i = 0; i < items.Length; i++) 
{
  if (i == index)
  {
    selection = items[i];
    break;
  }
}

Answer 6

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Answer 7

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