#include<cstring>
#include<fstream>
using namespace std;
ifstream f("palm.in");
ofstream g("palm.out");
int n,ii,jj,i,j,k,maxi;
char s[501];
int main()
{f>>s;
n=strlen(s)-1;
for(i=0;i<n;++i)
	for(j=i;j<=n;j+=2)
	{ii=i;
	jj=j;
	while(ii<=jj)
	{if(s[ii]!=s[jj])
		break;
	++ii;
	--jj;
	}
	if(ii<=jj)
		continue;
	for(k=(i+j)/2;k>i;--k)
		if(s[k]<s[k-1])
			break;
	if(k>i)
		continue;		
	if(j-i+1>maxi)
		maxi=j-i+1;
	}
g<<maxi<<'\n';
return 0;
}