import java.util.*;

public class Main {
	static Scanner sc = new Scanner(System.in);
	public static void main(String[] args) {
		String s = sc.next();
		
		//まずは、端以外の文字を中心にして調べる
		int ans1 = 0;
		for (int i=1; i<s.length()-1; i++) {
			StringBuilder sb = new StringBuilder(s);
			StringBuilder L = new StringBuilder(sb.delete(i,sb.length()));
			sb = new StringBuilder(s);
			StringBuilder R = new StringBuilder(sb.delete(0,i+1));
			L.reverse();
			
			int max1 = 0;
			for (int j=0; j<Math.min(L.length(),R.length()); j++) {
				if (L.charAt(j)==R.charAt(j)) {max1++;}
			}
			ans1 = Math.max(ans1,max1);
		}
		ans1 = ans1*2+1;
		
		
		//次、基準が文字の真ん中の場合
		int ans2 = 0;
		for (int i=1; i<s.length(); i++) {
			StringBuilder sb = new StringBuilder(s);
			StringBuilder L = new StringBuilder(sb.delete(i,sb.length()));
			sb = new StringBuilder(s);
			StringBuilder R = new StringBuilder(sb.delete(0,i));
			L.reverse();
			
			int max2 = 0;
			for (int j=0; j<Math.min(L.length(),R.length()); j++) {
				if (L.charAt(j)==R.charAt(j)) {max2++;}
			}
			ans2 = Math.max(ans2,max2);
		}
		ans2 = ans2*2;
		
		System.out.println(Math.max(ans1,ans2));
	}
}