#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vii;
typedef pair<int,int> pi;
typedef vector<pi> pii;
typedef tuple<ll,ll,ll> ti;
typedef vector<ll> li;
typedef vector<li> lii;
#define REP(i,a,b) for(int i=a;i<b;i++)
#define F first
#define S second
#define PB push_back
#define LSOne(s) ((s)&(-s))
ll INF=1000000000000000010;
int inf=1e9+10;
ll M=1e9+7;
int main() {
// ios::sync_with_stdio(0);
// cin.tie(0);
string s;cin>>s;
int n=s.size();
unordered_map<string,int> mp;
REP(i,0,n){
deque<char> a,b;
string t;
REP(j,i,n){
a.push_back(s[j]);
b.push_front(s[j]);
t.PB(s[j]);
if(a==b)mp[t]++;
}
}
int ans=0;
for(auto u:mp)ans=max(ans,u.S*(int)u.F.size());
cout<<ans;
}
