'''
A very basic check digit example
Pulled from a Systems Modeling Exam
Rules are.
User inputs two digit number where the first digit is greater than 1 (so first number being 10)
Input is split and the sum of the two digits is the check digit, if greater than 9 the new numbers are summed together
giving the check digit
Examples:
11 = 112 (because 1 + 1 is 2)
76 = 764 (because 7 + 6 is 13, 1 + 3 is 4)
'''
num = 10
while(num <= 99):
	num_list = list(str(num))
	sum = int(num_list[0]) + int(num_list[1])
	if(int(sum) > 9):
		c_list = list(str(sum))
		sum = int(c_list[0]) + int(c_list[1])
	print(str(num) + str(sum))
	num+=1