class Customer

   @@no_of_customers = 0

   def initialize(id, name, addr)

      @@no_of_customers += 1

      @cust_id = id

      @cust_name = name

      @cust_addr = addr

   end

   def display_details()

      puts "Customer id #@cust_id"

      puts "Customer name #@cust_name"

      puts "Customer address #@cust_addr"

   end

   def total_no_of_customers()

      puts "Total number of customers: #@@no_of_customers"

   end

end

​

# Create Objects

cust1 = Customer.new("1", "John", "GuangXi,NanNing")

cust2 = Customer.new("2", "Poul", "GuangDong,ShenZhen")

​

# Call Methods

cust1.display_details()

cust1.total_no_of_customers()

cust2.display_details()

cust2.total_no_of_customers()

​

Customer.new("3", "Raghu", "JiangSu,NanJing")

cust4 = Customer.new("4", "Rahman", "HuBei,WuHan")

cust4.total_no_of_customers()