Prime number program in Ruby

Write a prime number program in Ruby

Prime number is a number that is greater than 1 and divided by 1 or itself. In other words, prime numbers can't be divided by other numbers than itself or 1. For example 2, 3, 5, 7, 11, 13, 17.... are the prime numbers.

class PrimeNumber

  def checkPrime

     print "Enter the number: "

     num = gets.chomp.to_i

     check = 0 

     if (num == 0) || (num == 1)

       check = 1 

     else 

       (2..(num - 1)).each do |i|

         if (num % i == 0) && (i != num)

           check = 1 

           break

         end

       end

     end

    if check == 0  

      print "#{num} is a prime number"

    else

      print "#{num} is not a prime number"

    end 

  end

end

p = PrimeNumber.new 

p.checkPrime

Output:

Enter the number:  13
13 is a prime number