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#include<bits/stdc++.h>
using namespace std;
ostream& operator<<(ostream &out, string str) {
for(char c : str) out << c;
return out;
}
template<class L, class R> ostream& operator<<(ostream &out, pair<L, R> p) {
return out << "(" << p.first << ", " << p.second << ")";
}
template<class T> auto operator<<(ostream &out, T a) -> decltype(a.begin(), out) {
out << "{";
for(auto it = a.begin(); it != a.end(); it = next(it))
out << (it != a.begin() ? ", " : "") << *it;
return out << "}";
}
void dump() { cerr << "\n"; }
template<class T, class... Ts> void dump(T a, Ts... x) {
cerr << a << ", ";
dump(x...);
}
#ifdef DEBUG
# define debug(...) cerr << "[" #__VA_ARGS__ "]: ", dump(__VA_ARGS__)
#else
# define debug(...) false
#endif
#define REP(i, n) for(int i = 0; i < n; i++)
#define FOR(i, a, b) for(int i = a; i <= b; i++)
#define ST first
#define ND second
template<class T> int size(T && a) { return a.size(); }
using LL = long long;
using PII = pair<int, int>;
/*
* Opis: Tablica suffixowa
* Status: Cośtam potestowany
* Czas: O(n \log n)
* Użycie: SuffixArray t(s, lim) - lim to rozmiar alfabetu
* sa zawiera posortowane suffixy, zawiera pusty suffix
* lcp[i] to lcp suffixu sa[i - 1] i sa[i]
* Dla s = "aabaaab" sa = {6, 3, 0, 4, 1, 5, 2}, lcp = {0, 0, 3, 1, 2, 0, 1}
*/
struct SuffixArray {
vector<int> sa, lcp, rank;
SuffixArray(string& s, int lim = 256) { // lub basic_string<int>
int n = size(s) + 1, k = 0, a, b;
vector<int> x(s.begin(), s.end() + 1);
vector<int> y(n), ws(max(n, lim));
sa = lcp = rank = y;
iota(sa.begin(), sa.end(), 0);
for(int j = 0, p = 0; p < n; j = max(1, j * 2), lim = p) {
p = j;
iota(y.begin(), y.end(), n - j);
REP(i, n) if(sa[i] >= j)
y[p++] = sa[i] - j;
fill(ws.begin(), ws.end(), 0);
REP(i, n) ws[x[i]]++;
FOR(i, 1, lim - 1) ws[i] += ws[i - 1];
for(int i = n; i--;) sa[--ws[x[y[i]]]] = y[i];
swap(x, y);
p = 1, x[sa[0]] = 0;
FOR(i, 1, n - 1) a = sa[i - 1], b = sa[i], x[b] =
(y[a] == y[b] && y[a + j] == y[b + j]) ? p - 1 : p++;
}
FOR(i, 1, n - 1) rank[sa[i]] = i;
for(int i = 0, j; i < n - 1; lcp[rank[i++]] = k)
for(k && k--, j = sa[rank[i] - 1];
s[i + k] == s[j + k]; k++);
}
int operator[](int x) { return sa[x]; }
};
/*
* Opis: Drzewo punkt-przedział
* Czas: O(\log n)
* Pamięć : O(n)
* Użycie:
* Tree(n, val = 0) tworzy drzewo o n liściach, o wartościach val
* update(pos, val) zmienia element pos na val
* query(l, r) zwraca f na przedziale
* edytujesz funkcję f, można T ustawić na long longa albo parę
*/
struct Tree {
using T = int;
T f(T a, T b) { return min(a, b); }
vector<T> tree;
int size = 1;
Tree(int n, T val = 0) {
while(size < n) size *= 2;
tree.resize(size * 2, val);
}
void update(int pos, T val) {
tree[pos += size] = val;
while(pos /= 2)
tree[pos] = f(tree[pos * 2], tree[pos * 2 + 1]);
}
T query(int l, int r) {
l += size, r += size;
T ret = (l != r ? f(tree[l], tree[r]) : tree[l]);
while(l + 1 < r) {
if(l % 2 == 0)
ret = f(ret, tree[l + 1]);
if(r % 2 == 1)
ret = f(ret, tree[r - 1]);
l /= 2, r /= 2;
}
return ret;
}
};
/*
* Opis: radius[p][i] = $rad$ = największy promień palindromu
* parzystości p o środku i. $L=i-rad+!p, \; R=i+rad$ to palindrom.
* Dla [abaababaab] daje [003000020], [0100141000].
* Czas: O(n)
*/
array<vector<int>, 2> manacher(string &in) {
int n = size(in);
array<vector<int>, 2> radius = {{vector<int>(n - 1), vector<int>(n)}};
REP(parity, 2) {
int z = parity ^ 1, L = 0, R = 0;
REP(i, n - z) {
int &rad = radius[parity][i];
if(i <= R - z)
rad = min(R - i, radius[parity][L + (R - i - z)]);
int l = i - rad + z, r = i + rad;
while(0 <= l - 1 && r + 1 < n && in[l - 1] == in[r + 1])
++rad, ++r, --l;
if(r > R)
L = l, R = r;
}
}
return radius;
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
string str;
cin >> str;
int n = size(str);
SuffixArray sa(str);
Tree tree(n + 1);
FOR(i, 1, n - 1)
tree.update(i, sa.lcp[i]);
auto get_lcp = [&](int i, int j) {
if(i == j) return n - i;
i = sa.rank[i], j = sa.rank[j];
if(i > j) swap(i, j);
return tree.query(i + 1, j);
};
auto compare = [&](int a, int b, int i, bool equal) {
int l = get_lcp(a, i);
if(l >= b - a + 1) return equal;
if(i + l == n) return false;
return str[a + l] < str[i + l];
};
auto binsearch = [&](int a, int b, bool equal) {
int l = 1, r = n + 1;
while(l < r) {
int mid = (l + r) / 2;
if(compare(a, b, sa[mid], equal))
r = mid;
else
l = mid + 1;
}
return l;
};
auto count = [&](int a, int b) -> LL {
return binsearch(a, b, false) - binsearch(a, b, true);
};
auto m = manacher(str);
LL ans = 0;
REP(p, 2) REP(i, n + p - 1) {
int l = i - m[p][i] + 1 - p;
int r = i + m[p][i];
if(l <= r) ans = max(ans, count(l, r) * (r - l + 1));
}
cout << ans << "\n";
}
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