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CSharp · Console

/Program.cs

using System;
					
public class Program
{
	public static bool ePrimo(int num){
		int div = 0;
			
		for (int i = 1; i <= num; i++)
		{
			if (num % i == 0)
			{
				div++;
			}	
		}
		
		return div == 2;
	}
	
	public static void Main()
	{
        Random r = new Random();

        int p = r.Next(1, 100);

        while (!ePrimo(p))
        {
			p = r.Next(1,100);
        }
		
		Console.WriteLine(p);
	}
}