#include<stdio.h>
#include<string.h>
typedef long long ll;
int len,fin;
char x[100020];
int main(){
    scanf(" %s",x);
    len=strlen(x);
    for(fin=1;fin<=len;fin++){
        int l=len-fin,r=fin-1;
        if(l>r) continue;
        if(x[len/2]!=x[l]||x[len/2]!=x[r]) break;
    }
    printf("%d\n",fin-1);
}

### Prompt

In Cpp, your task is to solve 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<stdio.h>
#include<string.h>
typedef long long ll;
int len,fin;
char x[100020];
int main(){
    scanf(" %s",x);
    len=strlen(x);
    for(fin=1;fin<=len;fin++){
        int l=len-fin,r=fin-1;
        if(l>r) continue;
        if(x[len/2]!=x[l]||x[len/2]!=x[r]) break;
    }
    printf("%d\n",fin-1);
}

```