Find the sum of all the digits in all the integers between lowerBound and upperBound inclusive.

Input

Each line contains two integers lowerBound and upperBound (0 ≤ lowerBound ≤ upperBound ≤ 2 * 109).

Output

For each test case print in a separate line the sum of all the digits in all the integers between lowerBound and upperBound inclusive.