#include <bits/stdc++.h>
#pragma GCC optimize ("O2")
#pragma GCC optimize ("unroll-loops")
//#pragma GCC optimize("no-stack-protector,fast-math")
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<pii, int> piii;
typedef pair<ll, ll> pll;
#define debug(x) cerr<<#x<<'='<<(x)<<endl;
#define debugp(x) cerr<<#x<<"= {"<<(x.first)<<", "<<(x.second)<<"}"<<endl;
#define debug2(x, y) cerr<<"{"<<#x<<", "<<#y<<"} = {"<<(x)<<", "<<(y)<<"}"<<endl;
#define debugv(v) {cerr<<#v<<" : ";for (auto x:v) cerr<<x<<' ';cerr<<endl;}
#define all(x) x.begin(), x.end()
#define pb push_back
#define kill(x) return cout<<x<<'\n', 0;
const ld eps=1e-7;
const int inf=1000000010;
const ll INF=10000000000000010LL;
const int mod=1000000007;
const int MAXN=300010, LOG=21;
int n, m, k, u, v, x, y, t, a, b;
ll ans;
int Rank[MAXN<<1][LOG], P[MAXN<<1], pw;
int lcp[MAXN], L[MAXN], R[MAXN];
int seg[MAXN<<2];
int shit[MAXN<<1];
int rad[MAXN<<1], cnt[MAXN<<1];
vector<pii> vec[MAXN<<1], Q[MAXN<<1];
string S;
bool cmp(int x, int y){
if (Rank[x][pw-1]!=Rank[y][pw-1]) return Rank[x][pw-1]<Rank[y][pw-1];
if (max(x, y)+(1<<(pw-1))>=m) return x>y;
return Rank[x+(1<<(pw-1))][pw-1]<Rank[y+(1<<(pw-1))][pw-1];
}
inline void radix(){
memset(cnt, 0, sizeof(cnt));
for (int i=0; i<m; i++) cnt[shit[rad[i]=P[i]]]++;/*, mx=max(mx, shit[P[i]]);*/
int mx=0;
while (cnt[mx]!=m) cnt[mx+1]+=cnt[mx], mx++;
for (int i=m-1; ~i; i--) P[--cnt[shit[rad[i]]]]=rad[i];
}
void BuildSuffixArray(){
for (int i=0; i<m; i++) Rank[i][0]=S[i], P[i]=i;
for (pw=1; pw<LOG; pw++){
for (int i=0; i<m; i++) shit[i]=(i+(1<<(pw-1))>=m?0:Rank[i+(1<<(pw-1))][pw-1]);
radix();
for (int i=0; i<m; i++) shit[i]=Rank[i][pw-1];
radix();
//sort(P, P+m, cmp);
Rank[P[0]][pw]=1;
for (int i=1; i<m; i++) Rank[P[i]][pw]=Rank[P[i-1]][pw] + cmp(P[i-1], P[i]);
}
}
int GetLcp(int x, int y){
if (x>y) swap(x, y);
int res=0;
for (int i=LOG-1; ~i; i--) if (y<m && Rank[x][i]==Rank[y][i]){
x+=(1<<i);
y+=(1<<i);
res|=(1<<i);
}
return res;
}
void Maximize(int id, int tl, int tr, int l, int r, int val){
if (r<=tl || tr<=l) return ;
if (l<=tl && tr<=r){
seg[id]=max(seg[id], val);
return ;
}
int mid=(tl+tr)>>1;
Maximize(id<<1, tl, mid, l, r, val);
Maximize(id<<1 | 1, mid, tr, l, r, val);
}
int Get(int id, int tl, int tr, int pos){
if (pos<tl || tr<=pos) return seg[0];
if (tr-tl==1) return seg[id];
int mid=(tl+tr)>>1;
return max(seg[id], max(Get(id<<1, tl, mid, pos), Get(id<<1 | 1, mid, tr, pos)));
}
int main(){
ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
//freopen("65", "r", stdin);
//freopen("output.txt", "w", stdout);
cin>>S;
n=S.size();
S+="#";
for (int i=n-1; ~i; i--) S+=S[i];
m=S.size();
BuildSuffixArray();
for (int i=0; i<n; i++){
int len=GetLcp(i+1, 2*n-i);
ans=max(ans, 2ll*len);
vec[2*i+1].pb({i+1-len, i+1});
}
for (int i=0; i<n; i++){
int len=GetLcp(i, 2*n-i);
ans=max(ans, 2*len-1ll);
vec[2*i].pb({i-len+1, i+1});
}
int ted=0;
for (int i=0; i<m; i++) if (P[i]<n) P[ted++]=P[i];//, debug(P[i]);
for (int i=0; i+1<n; i++) lcp[i]=GetLcp(P[i], P[i+1]);
for (int i=0; i+1<n; i++) for (L[i]=i-1; ~L[i] && lcp[L[i]]>=lcp[i]; L[i]=L[L[i]]);
for (int i=n-2; ~i; i--) for (R[i]=i+1; R[i]<n-1 && lcp[R[i]]>=lcp[i]; R[i]=R[R[i]]);
for (int i=0; i<=n-2; i++){
ll ted=(R[i]-L[i]);
if (!ted) continue ;
Q[2*P[i]+lcp[i]].pb({P[i], ted});
}
memset(seg, -1, sizeof(seg));
for (int i=0; i<2*n; i++){
for (pii p:Q[i]) ans=max(ans, (Get(1, 0, n, p.first)-2*p.first+1ll)*p.second);
for (pii p:vec[i]) Maximize(1, 0, n, p.first, p.second, i);
}
cout<<ans<<'\n';
return 0;
}
/*
abaa
*/
