Score : $800$ points
For a positive integer $n$, we denote the integer obtained by reversing the decimal notation of $n$ (without leading zeroes) by $rev(n)$. For example, $rev(123) = 321$ and $rev(4000) = 4$.
You are given a positive integer $D$. How many positive integers $N$ satisfy $rev(N) = N + D$?
Input is given from Standard Input in the following format:
$D$
Print the number of the positive integers $N$ such that $rev(N) = N + D$.
63
2
There are two positive integers $N$ such that $rev(N) = N + 63$: $N = 18$ and $29$.
75
0
There are no positive integers $N$ such that $rev(N) = N + 75$.
864197532
1920