#include <bits/stdc++.h>
#define REP(i,n) for(int i=0;i<(n);++i)
using namespace std;
typedef long long ll;

int main() {
  string S;
  cin >> S;
  int slen = S.length();
  int ans = slen;
  REP(i,slen-1) {
    if (S[i] != S[i+1]) {
      ans = min( ans, max(slen-i-1, i+1) );
    }
  }
 cout << ans << endl;
}


### Prompt

Please formulate 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>
#define REP(i,n) for(int i=0;i<(n);++i)
using namespace std;
typedef long long ll;

int main() {
  string S;
  cin >> S;
  int slen = S.length();
  int ans = slen;
  REP(i,slen-1) {
    if (S[i] != S[i+1]) {
      ans = min( ans, max(slen-i-1, i+1) );
    }
  }
 cout << ans << endl;
}


```