3924.Little Elephant and Interval

Time Limit: 1s Memory Limit: 256MB

The Little Elephant very much loves sums on intervals.

This time he has a pair of integers l and r (l \le r). The Little Elephant has to find the number of such integers x (l \le x \le r), that the first digit of integer x equals the last one (in decimal notation). For example, such numbers as 101, 477474 or 9 will be included in the answer and 47, 253 or 1020 will not.

Help him and count the number of described numbers x for a given pair l and r.

Input Format(From the terminal/stdin)

The single line contains a pair of integers l and r (1 \le l \le r \le 1018) - the boundaries of the interval.

Please, do not use the %lld specifier to read or write 64-bit integers in C++. It is preferred to use cin, cout streams or the %I64d specifier.

Output Format(To the terminal/stdout)

On a single line print a single integer - the answer to the problem.

Sample Input 1

Copy
2 47
 ·  \n

Sample Output 1

Copy
12
  \n

Sample Input 2

Copy
47 1024
  ·    \n

Sample Output 2

Copy
98
  \n

Hints

In the first sample the answer includes integers 2, 3, 4, 5, 6, 7, 8, 9, 11, 22, 33, 44.

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