#include<bits/stdc++.h>
using namespace std;
int f(int n,string s){
	string w;
	for(int i=0;i<s.size();i++){
		w[n-i-1]=s[i];
	}
	if(w==s) return 1;
	else return 0;
}
int main(){
	int n;
	string s,j;
	cin>>s;
	n=s.size()/2;
	if(n*2==s.size()){
		j=s.substr(0,n);
		while(f(n,j)!=0){
			n/=2;
		}
		cout<<n/2;
	}
	else cout<<s.size();
	return 0;
}
/**************************************************************
	Problem: 1134
	User: houshanglin
	Language: C++
	Result: Wrong Answer
****************************************************************/