#include <stdio.h>
#include <string.h>

using namespace std;

int n,i,j,poz,mx,lung,st,dr;
char s[510];

int main () {
	freopen("palm.in","r",stdin);
	freopen("palm.out","w",stdout);
	gets(s+1);
	n=strlen(s+1);
	mx=1;
	for (i=1; i<=n; ++i) {
		poz=i;
		//caz impar:
		st=poz-1; dr=poz+1;
		lung=1;
		while (st>=1 && dr<=n) {
			if (s[st]==s[dr] && s[st]<=s[st+1]) {
				lung+=2;
				st--;
				dr++;
			}
			else break;
		}
		if (lung>mx) mx=lung;
		//caz par:
		st=poz; dr=poz+1;
		lung=0;
		while (st>=1 && dr<=n) {
			if ((s[st]==s[dr]) && ((st==poz) || (s[st]<=s[st+1]))) {
				lung+=2;
				st--;
				dr++;
			}
			else break;
		}
		if (lung>mx) mx=lung;
	}
	printf("%d\n",mx);
	return 0;
}