#include <iostream>
#include <fstream>
#include <string>

using namespace std ;

ifstream fin("palm.in") ;
ofstream fout("palm.out") ;

int main(){
	string s ;
	int n , sol = 0 ;
	fin >> s ;
	n = s.size() ;
	for(int i = 0 ; i < n ; i ++){
		int st = i - 1 , dr = i + 1 ;
		while(st >= 0 && dr < n && s[st] == s[dr] && s[st] <= s[st + 1] && s[dr] <= s[dr - 1]){
			st -- ;
			dr ++ ;
		}
		sol = max(sol , dr - st - 1) ;
		st = i - 1 ; dr = i ; 
		while(st >= 0 && dr < n && s[st] == s[dr] && s[st] <= s[st + 1] && s[dr] <= s[dr - 1]){
			st -- ;
			dr ++ ;
		}
		sol = max(sol , dr - st - 1) ; 
	}
	fout << sol ;
	fin.close() ;
	fout.close() ;
	return 0 ;
}