- Time limit: 1.00 s
- Memory limit: 512 MB
You are given a string s with length n and your task is to find the length of the maximum repeating prefix. A repeating prefix of s is a substring s[a\ldots b], 1 \le a \le b < n such that s[a\ldots b] = s[0\ldots b-a], that is s[a\ldots b] is equal to the prefix of s. The maximum repeating prefix is the longest of repeating prefixes.
Input
The first and only line of input contains string s with n characters between a-z. All letters are small case.
Output
Output the length of the maximum repeating prefix.
Limits
- 1 \le n \le 10^6
Example
Input:
abcdabcdabcd
Output:
8
Explanation:
The repeating prefix is abcdabcdabcd