Count Digit 2 Occurrences in a Range

Given a range ([L,R]) of integers, count the total number of times the digit (2) appears in all the numbers within that range. For example, in the range ([2,22]):

• Number 2 contains 1 occurrence of (2).
• Number 12 contains 1 occurrence of (2).
• Number 20 contains 1 occurrence of (2).
• Number 21 contains 1 occurrence of (2).
• Number 22 contains 2 occurrences of (2).

The total count in this example is 6.

inputFormat

The input consists of two space-separated integers (L) and (R) representing the inclusive bounds of the range.
Example: 2 22.

outputFormat

Output a single integer which is the total number of times the digit (2) appears in all the numbers from (L) to (R).

sample

2 22

6