Score : 300 points
Find the maximum possible sum of the digits (in base 10) of a positive integer not greater than N.
Input is given from Standard Input in the following format:
N
Print the maximum possible sum of the digits (in base 10) of a positive integer not greater than N.
100
18
For example, the sum of the digits in 99 is 18, which turns out to be the maximum value.
9995
35
For example, the sum of the digits in 9989 is 35, which turns out to be the maximum value.
3141592653589793
137