class AODigit:
	def increment():
		pass
	def decrement():
		pass
	def toString():
		pass

class ODigit(AODigit):
	def __init__(self, next):
		self.next=next
		self.i = 0

	def increment(self):
		self.i=(self.i+1) % 10
		if self.i==0:
			self.next.increment()
	def decrement(self):
		self.i=((self.i-1)+10) % 10
		if self.i==9:
			self.next.decrement()

	def toString(self):
		return self.next.toString()+str(self.i)

class OEnd(AODigit):
	def increment(self): 
		pass
	def toString(self):
		return ""
	def OEnd():
		pass

odometer=OEnd() #A 0 digit odometer
odometer=ODigit(odometer) # A 1 digit odometer
odometer=ODigit(odometer) # A 2 digit odometer
odometer=ODigit(odometer) # A 3 digit odometer
odometer=ODigit(odometer) # A 4 digit odometer

for i in range(5000):
	# Call the toString method of AODigit
	print odometer.toString()
	odometer.increment()

for i in range(10):
	# Call the toString method of AODigit
	print odometer.toString()
	odometer.decrement()