Strong number program in Ruby

Write a strong number program in Ruby

A number is called strong number if sum of the factorial of its digit is equal to number itself. For example: 145 since

1! + 4! + 5! = 1 + 24 + 120 = 145

class StrongNumber

  def checkStrong

     print "Enter the number: "

     input_num = gets.chomp.to_i

     num = input_num

     sum = 0 

     while num > 0 do

       rem = num % 10 

       num = num / 10 

       sum = sum + factorial(rem)

     end

     if input_num == sum

       print "#{input_num} is a strong number"

     else 

       print "#{input_num} is not a strong number"

     end 

  end

  

  private

  

  def factorial(a)

    fact = 1 

    (1..a).each do |i|

      fact = fact * i 

    end

    return fact

  end 

end

p = StrongNumber.new 

p.checkStrong

Output:

Enter the number:  145
145 is a strong number