Longest Palindromic Substring Length

Given a string s, your task is to find the length of the longest substring of s that is a palindrome. A palindrome is a string that reads the same backward as forward. Use the optimal algorithm to achieve this.

Note: The problem requires you to work with standard input and output. You should read the input from stdin and write the result to stdout. In your solution, if needed, you can use the following mathematical representation for the expansion process:

\( L = \text{right} - \text{left} - 1 \)

inputFormat

The input consists of a single line containing one string s (with no spaces) for which you have to determine the length of the longest palindromic substring.

For example:

babad

outputFormat

Output a single integer representing the length of the longest palindromic substring found in s.

For example, for the input above, the correct output is:

3

## sample

babad

3