Problems

# n-digit numbers

How many exist n-digit positive integers starting with digits a or b?

#### Input

Three integers are given: n (0 < n106), a and b. All data is given in decimal system.

#### Output

Print the number of n-digit positive integers starting with a or b.

Time limit 1 second
Memory limit 122.17 MiB
Input example #1
3 3 4

Output example #1
200