import java.util.*;
import java.lang.*;
import java.io.*;

class Ideone{
    public static void main(String[] args) throws Exception{
        // your code goes here
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String line = br.readLine();
        int max = line.length();
        int ans = 1;
        while(max-->0){
            for(int i=0;i<=line.length()-max;i++){
                if(check(line.substring(i,i+max))){
                    System.out.println(max);
                    return;
                }
            }
        }
        System.out.println(1);
    }
    public static boolean check(String line){
        int len = line.length();
        for(int i=0;i<len;i++){
            if(line.charAt(i) != line.charAt(len-i-1)){
                return false;
            }
        }
        return true;
    }
}