#include <bits/stdc++.h>
using namespace std;

int main(){
	string s;
	cin >> s;
	int ans = 1,check = 0;
	if(s.size() == 2) ans = 1;
	else{
		for(int i = 0; i < s.size(); i++){
			for(int j = i + 1; j < s.size(); j++){
				if(s[i] == s[j]){
					int x = j;
					for(int k = i; k <= (i+j)/2; k++){
						if(s[k] == s[x]) check = 1;
						else{
							check = 0;
							break;
						}
						x--;
					}
					if(check){
						ans = max(ans,j-i+1);
						check = 0;
					}
				}
			}
		}
	}
	if(ans == s.size()) ans -= 2;
	cout << ans << endl;
	return 0;
}