#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef double db;
typedef string str;
typedef pair<int,int> pi;
typedef pair<ll,ll> pl;
typedef pair<db,db> pd;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<db> vd;
typedef vector<str> vs;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<pd> vpd;
#define mp make_pair
#define f first
#define s second
#define sz(x) (int)x.size()
#define all(x) begin(x), end(x)
#define rall(x) (x).rbegin(), (x).rend()
#define rsz resize
#define ins insert
#define ft front()
#define bk back()
#define pf push_front
#define pb push_back
#define eb emplace_back
#define lb lower_bound
#define ub upper_bound
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define trav(a,x) for (auto& a: x)
const int MOD = 1e9+7; // 998244353;
const int MX = 2e5+5;
const ll INF = 1e18;
const ld PI = acos((ld)-1);
const int xd[4] = {1,0,-1,0}, yd[4] = {0,1,0,-1};
mt19937 rng((uint32_t)chrono::steady_clock::now().time_since_epoch().count());
template<class T> bool ckmin(T& a, const T& b) {
return b < a ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, const T& b) {
return a < b ? a = b, 1 : 0; }
int pct(int x) { return __builtin_popcount(x); }
int bits(int x) { return 31-__builtin_clz(x); } // floor(log2(x))
int cdiv(int a, int b) { return a/b+!(a<0||a%b == 0); } // division of a by b rounded up, assumes b > 0
int fstTrue(function<bool(int)> f, int lo, int hi) {
hi ++; assert(lo <= hi); // assuming f is increasing
while (lo < hi) { // find first index such that f is true
int mid = (lo+hi)/2;
f(mid) ? hi = mid : lo = mid+1;
}
return lo;
}
// INPUT
template<class A> void re(complex<A>& c);
template<class A, class B> void re(pair<A,B>& p);
template<class A> void re(vector<A>& v);
template<class A, size_t SZ> void re(array<A,SZ>& a);
template<class T> void re(T& x) { cin >> x; }
void re(db& d) { str t; re(t); d = stod(t); }
void re(ld& d) { str t; re(t); d = stold(t); }
template<class H, class... T> void re(H& h, T&... t) { re(h); re(t...); }
template<class A> void re(complex<A>& c) { A a,b; re(a,b); c = {a,b}; }
template<class A, class B> void re(pair<A,B>& p) { re(p.f,p.s); }
template<class A> void re(vector<A>& x) { trav(a,x) re(a); }
template<class A, size_t SZ> void re(array<A,SZ>& x) { trav(a,x) re(a); }
// TO_STRING
#define ts to_string
str ts(char c) { return str(1,c); }
str ts(bool b) { return b ? "true" : "false"; }
str ts(const char* s) { return (str)s; }
str ts(str s) { return s; }
template<class A> str ts(complex<A> c) {
stringstream ss; ss << c; return ss.str(); }
str ts(vector<bool> v) {
str res = "{"; F0R(i,sz(v)) res += char('0'+v[i]);
res += "}"; return res; }
template<size_t SZ> str ts(bitset<SZ> b) {
str res = ""; F0R(i,SZ) res += char('0'+b[i]);
return res; }
template<class A, class B> str ts(pair<A,B> p);
template<class T> str ts(T v) { // containers with begin(), end()
bool fst = 1; str res = "{";
for (const auto& x: v) {
if (!fst) res += ", ";
fst = 0; res += ts(x);
}
res += "}"; return res;
}
template<class A, class B> str ts(pair<A,B> p) {
return "("+ts(p.f)+", "+ts(p.s)+")"; }
// OUTPUT
template<class A> void pr(A x) { cout << ts(x); }
template<class H, class... T> void pr(const H& h, const T&... t) {
pr(h); pr(t...); }
void ps() { pr("\n"); } // print w/ spaces
template<class H, class... T> void ps(const H& h, const T&... t) {
pr(h); if (sizeof...(t)) pr(" "); ps(t...); }
// DEBUG
void DBG() { cerr << "]" << endl; }
template<class H, class... T> void DBG(H h, T... t) {
cerr << ts(h); if (sizeof...(t)) cerr << ", ";
DBG(t...); }
#ifdef LOCAL // compile with -DLOCAL
#define dbg(...) cerr << "LINE(" << __LINE__ << ") -> [" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)
#else
#define dbg(...) 0
#endif
// FILE I/O
void setIn(string s) { freopen(s.c_str(),"r",stdin); }
void setOut(string s) { freopen(s.c_str(),"w",stdout); }
void unsyncIO() { ios_base::sync_with_stdio(0); cin.tie(0); }
void setIO(string s = "") {
unsyncIO();
// cin.exceptions(cin.failbit);
// throws exception when do smth illegal
// ex. try to read letter into int
if (sz(s)) { setIn(s+".in"), setOut(s+".out"); } // for USACO
}
/**
* Description: insert int, query max xor with some int in the trie
* Time: O(MXBIT)
* Source: CF Algorithms Gym
* Verification: January Easy 2018 - Shubham and Subarray Xor
*/
template<int MX> struct Trie {
int nex[MX][27], sz[MX], num = 0; // num is last node in trie
int par[MX][30];
Trie() { memset(nex,0,sizeof nex); memset(sz,0,sizeof sz); }
int trans(int node, int c){
if(nex[node][c] == 0){
nex[node][c] = ++num;
par[num][0] = node;
for(int i = 1; i < 30; i++){
par[num][i] = par[par[num][i-1]][i-1];
}
}
return nex[node][c];
}
int getpar(int node, int red){
for(int i = 30-1; i >= 0; i--){
if((1<<i) <= red){
red-=(1<<i);
node = par[node][i];
}
}
return node;
}
ll traverse(int node = 0, int depth = -1){ //mode 1 --> odd, mode 2 --> even
ll curans = 0;
for(int i = 0; i < 27; i++){
if(nex[node][i] == 0) continue;
ckmax(curans, traverse(nex[node][i], depth+1));
sz[node]+=sz[nex[node][i]];
}
ckmax(curans, ll(sz[node])*depth);
//dbg(node, sz[node], depth);
return curans;
}
};
Trie<600105> t;
/**
* Source: http://codeforces.com/blog/entry/12143
* Time: O(N)
* Description: length of largest palindrome centered at each character of string
* and between every consecutive pair
* Verification: http://www.spoj.com/problems/MSUBSTR/
*/
ll manacher(str s) {
str s1;
s1+=char('a'+26); trav(c,s) s1 += c, s1 += char('a'+26);
vpi ans(sz(s1)); //length, node in trie
int lo = -1, hi = -1;
for(int i = 0; i < sz(s1); i++){
int len = 0;
int node = t.trans(0, s1[i]-'a');
if(hi < i){
//dbg(i, "1");
}
else{
if(ans[hi+lo-i].f <= hi-i){
//dbg(i, "2");
len = ans[hi+lo-i].f;
node = ans[hi+lo-i].s;
}
else{
//dbg(i, "3");
len = hi-i;
node = t.getpar(node, ans[hi+lo-i].f-(hi-i));
}
}
//dbg(len, node);
while(i-len-1 >= 0 && i+len+1 < sz(s1)){
if(s1[i-len-1] == s1[i+len+1]){
len++;
//dbg(node);
node = t.trans(node, s1[i+len]-'a');
}
else break;
}
ans[i] = mp(len, node);
t.sz[node]++;
if(i+ans[i].f > hi) lo = i-ans[i].f, hi = i+ans[i].f;
//dbg(ans[i], lo, hi);
}
//dbg(ans);
return t.traverse();
}
/// Usage: ps(manacher("abacaba"))
int main() {
setIO();
string s; cin>> s; ps(manacher(s));
// you should actually read the stuff at the bottom
}
/* stuff you should look for
* int overflow, array bounds
* special cases (n=1?)
* do smth instead of nothing and stay organized
* WRITE STUFF DOWN
*/
