A8617. Little Elephant and Interval

The Little Elephant very much loves sums on intervals.

This time he has a pair of integers $l$ and $r$ $(l<=r)$ . The Little Elephant has to find the number of such integers $x$ $(l<=x<=r)$ , 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 $r$ .

The single line contains a pair of integers $l$ and $r$ $(1<=l<=r<=10^{18})$ — the boundaries of the interval.

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

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

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