Prime Number in C#

Q. 1 What is Prime Number?

Answer:  A prime number (or a prime) is a natural number greater than 1 that has no positive divisors other than 1 and itself. 

Q. 2 Write a program in C# to check number is prime or not ?

Answer: The following code snippet to check prime number or not.

using System;

namespace PrimeNumber
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Enter a number");
            int number = Convert.ToInt32(Console.ReadLine());
            bool isPrime = IsPrime(number);
            if (isPrime)
            {
                Console.WriteLine("{0} is a prime number", number);
            }
            else
            {
                Console.WriteLine("{0} is not a prime number", number);
            }
            Console.Read();
        }

        private static bool IsPrime(int number)
        {
            for (int i = 2; i <= Math.Sqrt(number); i++)
            {
                if (number % i == 0)
                {
                    return false;
                }
            }
            return true;
        }
    }
}

C#

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