#include <bits/stdc++.h>
using namespace std;
#define F first
#define S second
#define PB push_back
#define ll long long
#define _sz(e) e.size()
#define pii pair <int , int>
#define FAST ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#pragma GCC target("sse4,avx,avx2")
#pragma GCC optimize("O3,unroll-loops")
const ll maxn = 1e5 + 8 , N = 200 + 8 , base = 301 , mod = 1e9 + 7 , INF = 1e18;
unordered_map <int , int> mp;
ll n , h[maxn] , hrev[maxn] , pbase[maxn];
string s;
void pre() {
pbase[0] = 1;
for (int i = 1; i < maxn; ++i) {
pbase[i] = (pbase[i - 1] * base) % mod;
}
for (int i = 1; i <= n; ++i) {
h[i] = (h[i - 1] * base + s[i - 1]) % mod;
}
for (int i = n; i >= 1; --i) {
hrev[i] = (hrev[i + 1] * base + s[i - 1]) % mod;
}
}
int HASH(int l , int r) {
return (h[r] - (h[l] * pbase[r - l] % mod) + mod) % mod;
}
int HASHrev(int l , int r) {
return (hrev[l + 1] - (hrev[r + 1] * pbase[r - l] % mod) + mod) % mod;
}
bool palindrome(int l , int r) {
int mid = (l + r) / 2;
if((r - l) & 1) {
if(r - l == 1) return 1;
return (HASH(l , mid) == HASHrev(mid + 1 , r));
}
return (HASH(l , mid) == HASHrev(mid , r));
}
int main() {
FAST;
cin >> s; n = _sz(s);
pre();
ll ans = 0;
for (int i = 0; i < n; ++i) {
for (int j = i + 1; j <= n; ++j) {
if(!palindrome(i , j)) continue;
// cout << i << ' ' << j << endl;
mp[HASH(i , j)]++;
}
}
for (int i = 0; i < n; ++i) {
for (int j = i + 1; j <= n; ++j) {
if(!palindrome(i , j)) continue;
ans = max(ans , 1ll * mp[HASH(i , j)] * (j - i));
}
}
cout << ans << '\n';
}
