Problem:
Score : 500 points

Problem Statement

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.

Sample Input 1

010

Sample Output 1

2

We can turn all the characters of S into 0 by the following operations:

Perform the operation on the segment S[1,3] with length 3. S is now 101.

Perform the operation on the segment S[1,2] with length 2. S is now 011.

Perform the operation on the segment S[2,3] with length 2. S is now 000.

Sample Input 2

100000000

Sample Output 2

8

Sample Input 3

00001111

Sample Output 3

4

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Runtime Error)

import java.util.*;
public class Main {
    public static void main(String [] args) {
        Scanner sc = new Scanner(System.in);
        String S;
        S = sc.next();
        char [] list = new char[S.length()];
        ArrayList<Integer> list2 = new ArrayList<Integer>();
        for(int a=0;a<S.length();a++){
            list[a] = S.charAt(a);
        }
        for(int a=0;a<S.length()-1;a++){
            if((list[a]=='1'&&list[a+1]=='0')||(list[a]=='0'&&list[a+1]=='1')){
                int num=S.length()-(a+1);
                if(num>a){
                    for(int b=a+1;b<S.length();b++){
                           if(list[a] =='1') list[a] ='0';
                        else list[a] ='1';
                    }
                    if(num!=1) list2.add(num);
                }
                else if(num<=a){
                    if(a!=0)list2.add(a+1);
                }
            }
        }
        System.out.println(Collections.min(list2));
    }
}