Login In the first and only line are written two integers L and R (1000 ≤ L ≤ R ≤ 9999), which denote the limits of the range.

Exit
On standard output, print how many numbers in the given range (numbers that are either greater than or equal to L and less than or equal to R) the digits are in ascending order.

Limits
Time limit: 1 second
Memory limit: 64 megabytes

Examples

input 1345 1345
exit 1

input 1310 1319

exit 0

input 1233 1245

exit 7

Explanation for the third test example: These are the numbers 1234, 1235, 1236, 1237, 1238, 1239 and 1245.