Challenge: Find the Largest Number

Problem statement

A girl lost the key to her locker (Note: The key is only numeric). She remembers the number of digits N and the sum S of all the digits of her password. She also knows that her password is the largest number of N digits that can be possible with the given sum S.

Implement a function that helps her retrieve her key.

Input

The inputs are the number of digits and the sum of those digits.

Output

The output prints the largest number that can be created (or the key).

Sample input

number_of_digits = 3, sum_of_digits = 20 

Sample output

992

Note: If no number is possible for a combination of sum_of_digits and number_of_digits, then simply print None.