# include <bits/stdc++.h>

char s [123456] ;

int main ( )  {
	scanf ( "%s", s ) ;

	int n = strlen ( s ) ;

	int ans ( INT_MAX ) ;
	
	for ( int i = 0 ; i < n - 1 ; ++ i )  {
		if ( s [i] ^ s [i + 1] )  ans = std :: min ( ans, std :: max ( i + 1, n - i - 1 ) ) ;
	}

	return ! printf ( "%d\n", ans != INT_MAX ? ans : n ), 0 ;
}

### Prompt

Your challenge is to write a cpp solution to the following problem:

You are given a string S consisting of `0` and `1`. Find the maximum integer K not greater than |S| such that we can turn all the characters of S into `0` by repeating the following operation some number of times.

* Choose a contiguous segment [l,r] in S whose length is at least K (that is, r-l+1\geq K must be satisfied). For each integer i such that l\leq i\leq r, do the following: if S_i is `0`, replace it with `1`; if S_i is `1`, replace it with `0`.

Constraints

* 1\leq |S|\leq 10^5
* S_i(1\leq i\leq N) is either `0` or `1`.

Input

Input is given from Standard Input in the following format:


S


Output

Print the maximum integer K such that we can turn all the characters of S into `0` by repeating the operation some number of times.

Examples

Input

010


Output

2


Input

100000000


Output

8


Input

00001111


Output

4

### Response

```cpp
# include <bits/stdc++.h>

char s [123456] ;

int main ( )  {
	scanf ( "%s", s ) ;

	int n = strlen ( s ) ;

	int ans ( INT_MAX ) ;
	
	for ( int i = 0 ; i < n - 1 ; ++ i )  {
		if ( s [i] ^ s [i + 1] )  ans = std :: min ( ans, std :: max ( i + 1, n - i - 1 ) ) ;
	}

	return ! printf ( "%d\n", ans != INT_MAX ? ans : n ), 0 ;
}

```