CSharp_H3_PrimeNumber

using System;

class WhetherIsPrime
{
    static void Main()
    {
        Console.WriteLine("Please enter positive integer <=100:");
        int positiveInt = int.Parse(Console.ReadLine());
        if (positiveInt > 100 | positiveInt < 0) //Checks whether input conditions are met.
        {
            Console.WriteLine("Invalid number. Please enter positive integer <=100:");

        }
        else
        {

            int sumDividers = 0; //This is the counter of dividers. If it remains zero at the end the integer is prime.
            for (int i = 2; i <= Math.Sqrt(positiveInt); i++)
            {
                if (positiveInt % i == 0)
                {
                    sumDividers = sumDividers + 1;
                }
            }
            Console.WriteLine(sumDividers == 0 ? "The number is prime." : "The number is not prime.");
        }
    }
}