Given an integer n, find two integers a and b such that:
A) a >= 0 and b >= 0
B) a + b = n
C) DigitSum(a) + Digitsum(b) is maximum of all possibilities.
You will return the digitSum(a) + digitsum(b).
For example:
solve(29) = 11. If we take 15 + 14 = 29 and digitSum = 1 + 5 + 1 + 4 = 11. There is no larger outcome.
n will not exceed 10e10.
More examples in test cases.