Description

Original source: SCOI 2009

Windy has defined a type of number called a Windy number: a positive integer without leading zeros and where the absolute difference between every pair of adjacent digits is at least $2$.

Windy wants to know how many Windy numbers exist between $A$ and $B$, inclusive.

Input Format

One line containing two numbers, $A$ and $B$.

Output Format

Output a single integer representing the answer.

Sample 1

1 10

9

Sample 2

25 50

20

Data Range and Hints

$20\%$ of the data satisfies $1\le A\le B\le 10^6$;
$100\%$ of the data satisfies $1\le A\le B\le 2\times 10^9$.