// created by Dinh Manh Hung
// onepunchac168
// THPT CHUYEN HA TINH
// HA TINH, VIET NAM
// Grandmaster go go
#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3,unroll-loops,no-stack-protector")
#pragma GCC target("sse4,avx2,fma")
#define task "palindrome"
#define ldb long double
#define pb push_back
#define fi first
#define se second
#define pc pop_back()
#define all(x) begin(x),end(x)
#define uniquev(v) v.resize(unique(all(v))-v.begin())
#define FOR(i,a,b) for (int i=a;i<=b;i++)
#define cntbit(v) __builtin_popcountll(v)
#define gcd(a,b) __gcd(a,b)
#define lcm(a,b) ((1LL*a*b)/__gcd(a,b))
#define mask(x) (1LL<<(x))
#define readbit(x,i) ((x>>i)&1)
#define ins insert
typedef long long ll;
typedef pair <ll,ll> ii;
typedef pair <ll,ii> iii;
typedef pair <ii,ii> iiii;
ll dx[]= {1,-1,0,0,1,-1,1,-1};
ll dy[]= {0,0,-1,1,1,-1,-1,1};
const ldb PI = acos (-1);
const long long mod=978846151;
const long long base=29;
const long long mod1=1e9+9;
const long long base1=31;
const int maxn=1e6+5;
//const int mod=1e9+7;
const char nl = '\n';
inline int ReadInt()
{
char co;
for (co = getchar(); co < '0' || co > '9'; co = getchar());
int xo = co - '0';
for (co = getchar(); co >= '0' && co <= '9'; co = getchar())
xo = xo * 10 + co - '0';
return xo;
}
void WriteInt(int xo)
{
if (xo > 9)
WriteInt(xo / 10);
putchar(xo % 10 + '0');
}
/* END OF TEMPLATE*/
// ================= Solution =================//
ll q;
string ss;
ll n;
long long T[600005];
long long F[600005];
ll Tb[600005];
ll Fb[600005];
ll id[600005];
ii lcp[600005];
ll res;
struct SuffixArray {
static const int maxn = 6e5 + 5;
static const char sep = '$';
int n;
char s[maxn];
int sa[maxn], ra[2][maxn];
int lcp[maxn];
void build(string t) {
n=t.size();
for (int i=0;i<n;i++)
{
s[i]=t[i];
}
for (int i = 0; i < n; i++) {
sa[i] = i, ra[0][i] = 0, ra[1][i] = s[i] + 1;
}
for (int d = 1; radixsort(); d <<= 1) {
for (int i = 0; i < n; i++) {
if (i + d < n) {
ra[1][i] = ra[0][i + d] + 1;
} else {
ra[1][i] = 0;
}
}
}
buildlcp();
}
int radixsort() {
static int p[maxn];
static int tmpsa[maxn];
static int tmpra[maxn];
int mx = max(1024, n) + 1;
for (int step = 1; step >= 0; step--) {
fill_n(p, mx, 0);
for (int i = 0; i < n; i++) {
p[ra[step][i] + 1]++;
tmpsa[i] = sa[i];
}
partial_sum(p, p + mx, p);
for (int i = 0; i < n; i++) {
sa[p[ra[step][tmpsa[i]]]++] = tmpsa[i];
}
}
int ptr = 0;
tmpra[sa[0]] = ptr;
for (int i = 1; i < n; i++) {
int u = sa[i - 1];
int v = sa[i];
if (ra[0][u] < ra[0][v] || ra[1][u] < ra[1][v]) {
ptr++;
}
tmpra[v] = ptr;
}
for (int i = 0; i < n; i++)
ra[0][i] = tmpra[i];
return ptr < n - 1;
}
void buildlcp() {
for (int i = 0, k = 0; i < n; i++) {
if (!ra[0][i])
lcp[ra[0][i]] = 0;
else {
for (int j = sa[ra[0][i] - 1]; s[i + k] == s[j + k] && s[i + k] != sep;
k++)
;
lcp[ra[0][i]] = k;
k = max(k - 1, 0);
}
}
}
} sta;
ii HASH(int u,int v)
{
return {(T[v]-T[u-1]*F[v-u+1]+mod*mod)%mod,(Tb[v]-Tb[u-1]*Fb[v-u+1]+mod1*mod1)%mod1};
}
ll LCP(int u,int v)
{
if (u>v)
{
swap(u,v);
}
ll kq=0;
int lefta=1;int righta=n-v+1;
while (lefta<=righta)
{
int mid=(lefta+righta)/2;
if (HASH(u,u+mid-1)==HASH(v,v+mid-1))
{
kq=mid;
lefta=mid+1;
}
else righta=mid-1;
}
return kq;
}
bool cmp(int u,int v)
{
int cnt=LCP(u,v);
return ss[u+cnt]<ss[v+cnt];
}
struct DSU{
ll lab[600005];
ll sz[600005];
void makeset(int u)
{
lab[u]=-1;
sz[u]=1;
}
ll findset(int u)
{
if (lab[u]<0){return u;}
return lab[u]=findset(lab[u]);
}
void Union(int r,int s)
{
if (lab[r]>lab[s])
{
swap(r,s);
}
lab[r]+=lab[s];
lab[s]=r;
sz[r]+=sz[s];
}
};
DSU dsu;
vector<int> manacher_odd(string sa) {
int na = sa.size();
sa = "$" + sa + "^";
vector<int> p(na + 2);
int l = 1, r = 1;
for(int i = 1; i <= na; i++) {
p[i] = max(0, min(r - i, p[l + (r - i)]));
while(sa[i - p[i]] == sa[i + p[i]]) {
p[i]++;
}
if(i + p[i] > r) {
l = i - p[i], r = i + p[i];
}
}
return vector<int>(begin(p) + 1, end(p) - 1);
}
vector<ll> manacher(string sa) {
string t;
for(auto c: sa) {
t.pb('#');
t.pb(c);
}
auto res = manacher_odd(t + "#");
return vector<ll>(begin(res) + 1, end(res) - 1);
}
ll ip[600005];
ll Ta[600005*4];
void update(int node,int l,int r ,int u,ll val)
{
if (u>r||u<l)
{
return;
}
if (l==r)
{
Ta[node]=val;
return;
}
update(node*2,l,(l+r)/2,u,val);
update(node*2+1,(l+r)/2+1,r,u,val);
Ta[node]=min(Ta[node*2],Ta[node*2+1]);
}
vector <ll> T1;
ll query(int node,int l,int r,int u,int v,ll val)
{
if (l>v||r<u)
{
return -1;
}
if (Ta[node]>=val)
{
return -1;
}
if (l==r)
{
return l;
}
int mid=(l+r)/2;
int res=-1;
if (Ta[node*2+1]<val)
{
res=query(node*2+1,mid+1,r,u,v,val);
}
if (res==-1)
{
res=query(node*2,l,mid,u,v,val);
}
return res;
}
ll coderneverdie(int id,int limit)
{
ll aa=query(1,1,T1.size(),id,limit,id);
return aa-id+1;
}
void optmushnpr()
{
cin>>ss;
sta.build(ss);
ll ss_sum=0;
n=ss.size();
T1=manacher(ss);
ll dem=0;
for (int i=0;i<T1.size();i+=2)
{
dem++;
ip[dem]=i+1;
}
for (int i=0;i<T1.size();i++)
{
update(1,1,T1.size(),i+1,i+1-T1[i]);
}
ss=' '+ss;
T[0]=0;
F[0]=1;
Tb[0]=0;
Fb[0]=1;
res=1e9+5;
for (int i=1;i<=n;i++)
{
T[i]=(T[i-1]*base+ss[i]-'a'+1)%mod;
F[i]=(F[i-1]*base)%mod;
Tb[i]=(Tb[i-1]*base1+ss[i]-'a'+1)%mod1;
Fb[i]=(Fb[i-1]*base1)%mod1;
dsu.makeset(i);
ll a1=ip[i];
ll a2=ip[n];
a2=a1+((a2-a1)/2);
ss_sum=max(ss_sum,coderneverdie(a1,a2));
}
//sort (id+1,id+n+1,cmp);
for (int i = 0; i < sta.n; i++)
{
id[sta.ra[0][i]+1]=i+1;
}
for (int i=1;i<=n-1;i++)
{
//assert(id[i]!=0||id[i+1]!=0);
//assert(cmp(id[i],id[i+1])==true);
lcp[i].fi=LCP(id[i],id[i+1]);
lcp[i].se=i;
}
sort (lcp+1,lcp+n);
for (int i=n-1;i>=1;i--)
{
ii aa=lcp[i];
if (aa.fi==0)
{
break;
}
int r=dsu.findset(id[aa.se]);
int s=dsu.findset(id[aa.se+1]);
if (r!=s)
{
dsu.Union(r,s);
}
//cout<<aa.fi<<" "<<res<<" "<<id[aa.se]<<" "<<id[aa.se+1]<<'\n';
ll opt=dsu.findset(id[aa.se]);
ll a1=ip[id[aa.se]];
ll a2=ip[id[aa.se]+aa.fi-1];
a2=a1+((a2-a1)/2);
ll ansa=coderneverdie(a1,a2);
ll po=dsu.sz[opt];
ss_sum=max(ss_sum,ansa*po);
}
cout<<ss_sum;
}
signed main()
{
ios_base::sync_with_stdio(false);
cin.tie(0);
if (fopen(task".inp","r")){
freopen(task".inp","r",stdin);
freopen(task".out","w",stdout);}
int t;
t=1;
while (t--){optmushnpr();}
}
// goodbye see ya
