java

import java.util.*;
public class Main {
    public static void main(String[] arg) {
        Scanner s = new Scanner(System.in);
        while (s.hasNext()) {
            String input = s.nextLine();
            StringBuilder sb = new StringBuilder(input);
            StringBuilder sbReverse = new StringBuilder(sb.reverse());
            int count = 0;
            int tempCount = 0;
            for (int i = 0; i < input.length(); i++) {
                if (input.charAt(i) != sbReverse.charAt(i)) {
                    tempCount = 0;
                } else {
                    tempCount = tempCount + 1;
                    count = Math.max(count, tempCount);
                }
            }
            System.out.println(count);
        }
    }
}