Description

We call an integer incremental number if it reads strictly incremental from left to right.

For example:

$8, 37, 1356$ are all incremental numbers

$11, 32, 1517$ are not incremental numbers.

Please compute: given $a$ and $b$, how many increasing numbers are in $a,a+1, a+2, ..., b$.

Input Format:

A line of two integers $a$, $b$

Output format:

One integer representing the number of incremental numbers in the interval $[a,b]$.

Constraint:

$1 \le a \le b \le 100000$

Input Example:

1 11

Output Example:

9