Distributed probability random number generator

Question

I want to generate a number based on a distributed probability. For example, just say there are the following occurences of each numbers:

Number| Count               


        

Answer 1

Thanks for all your solutions guys! Much appreciated!

@Menjaraz I tried implementing your solution as it looks very resource friendly, however had some difficulty with the syntax.

So for now, I just transformed my summary into a flat list of values using LINQ SelectMany() and Enumerable.Repeat().

public class InventoryItemQuantityRandomGenerator
{
    private readonly Random _random;
    private readonly IQueryable _quantities;

    public InventoryItemQuantityRandomGenerator(IRepository database, int max)
    {
        _quantities = database.AsQueryable()
            .Where(x => x.Quantity <= max)
            .GroupBy(x => x.Quantity)
            .Select(x => new
                             {
                                 Quantity = x.Key,
                                 Count = x.Count()
                             })
            .SelectMany(x => Enumerable.Repeat(x.Quantity, x.Count));

        _random = new Random();
    }

    public int Next()
    {
        return _quantities.ElementAt(_random.Next(0, _quantities.Count() - 1));
    }
}