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Problem 2070 Beautiful number

## Problem Description

Seen is an odd boy and his taste is strange as well. It seems to him that a positive integer number is beautiful if and only if the sum of first half of the digits of it equal to the sum of after half of the digits of it. If a number have n digits, first half of the digits of it is the digits of first n/2.For example, 45 and123 are not beautiful numbers. 1423 and 321 are beautiful numbers. We will not argue with this and just count the quantity of beautiful numbers in given ranges.

## Input

The first line of the input contains the number of cases t. Each of the next t lines contains two natural numbers li and ri (1 ≤ li ≤ ri ≤ 9*10^18) .

## Output

Output should contain t numbers — answers to the queries, one number per line — quantities of beautiful numbers in given intervals (from li to ri, inclusively).

## Sample Input

3 1 10 1 100 1 200

0 9 11

## Source

FOJ有奖月赛-2011年12月

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