Description

The girl gives two integers $L$ and $R$, and she wants Huan-zong to count how many integers $X$ satisfy:

• $L \le X \le R$,
• The most significant and least significant decimal digits of $X$ are equal.

For example (ignoring the restriction $L \le X \le R$), $2$, $101$, $329873$ qualify, whereas $23$ and $4567$ do not.

Children, Huan-zong’s happiness in his next life depends on your help!

Input Format

One line containing two integers $L$ and $R$.

Output Format

One line with a single integer, the number of $X$ that satisfy the property.

2 47

12

Hint

Constraints:

For $50\%$ of the testdata, $1 \le L \le R \le 10^6$.

For $100\%$ of the testdata, $1 \le L \le R \le 10^{18}$.

Translated by ChatGPT 5