#include<stdio.h>
#include<string.h>
char s[600];
int main()
{
	freopen("palm.in","r",stdin);
	freopen("palm.out","w",stdout);
	int len,i,l,lmax=1,st,dr;
	gets(s);
	len=strlen(s);
	for(i=1;i<len;i++)
	{
		l=1;
		st=i-1;
		dr=i+1;
		while(st>=0&&dr<=len&&s[st]==s[dr]&&s[st]<s[st+1])
		{
			l+=2;
			st--;
			dr++;
		}
		if(l>lmax)
			lmax=l;
	}
	printf("%d\n",lmax);
	return 0;
}