#include <bits/stdc++.h>
using namespace std;
void just_do_it();
int main() {
#ifdef KAMIRULEZ
freopen("kamirulez.inp", "r", stdin);
freopen("kamirulez.out", "w", stdout);
#endif
ios_base::sync_with_stdio(0);
cin.tie(0);
just_do_it();
return 0;
}
const int maxn = 3e5 + 20;
const int maxL = 20;
int pal[maxn * 2];
int a[maxn * 2];
int eq[maxn];
pair<int, int> pair_eq[maxn];
int nxt_eq[maxn];
int pos[maxn];
int perm[maxn];
int nxt_perm[maxn];
int lcp[maxn];
vector<pair<int, int>> q_join[maxn];
vector<int> q_add[maxn];
int sz[maxn];
int depth[maxn];
int par[maxn];
int root(int u) {
if (par[u] == -1) {
return u;
}
return (par[u] = root(par[u]));
}
void update(int u, int v) {
int ru = root(u);
int rv = root(v);
if (ru == rv) {
return;
}
if (depth[ru] > depth[rv]) {
swap(ru, rv);
}
par[ru] = rv;
sz[rv] += sz[ru];
if (depth[ru] == depth[rv]) {
depth[rv]++;
}
return;
}
void just_do_it() {
string s;
cin >> s;
int n = s.size();
for (int i = 0; i < n * 2 + 1; i++) {
if (i % 2 == 1) {
a[i] = s[i / 2] - 'a';
}
else {
a[i] = -1;
}
}
int lt = -1;
int rt = -1;
for (int i = 0; i < n * 2 + 1; i++) {
pal[i] = (i <= rt ? min(rt - i + 1, pal[lt + rt - i]) : 0);
while (i - pal[i] >= 0 && i + pal[i] < n * 2 + 1 && a[i - pal[i]] == a[i + pal[i]]) {
pal[i]++;
}
if (i + pal[i] - 1 > rt) {
lt = i - pal[i] + 1;
rt = i + pal[i] - 1;
}
}
for (int i = 0; i < n; i++) {
a[i] = s[i] - 'a' + 1;
}
a[n++] = 0;
for (int i = 0; i < n; i++) {
pos[a[i]]++;
}
int cnt = 0;
for (int i = 0; i <= 26; i++) {
swap(cnt, pos[i]);
cnt += pos[i];
}
for (int i = 0; i < n; i++) {
perm[pos[a[i]]++] = i;
}
cnt = 0;
for (int i = 0; i < n; i++) {
if (i > 0 && a[perm[i - 1]] != a[perm[i]]) {
cnt++;
}
eq[perm[i]] = cnt;
}
for (int k = 0; k < maxL; k++) {
for (int i = 0; i < n; i++) {
pos[i] = 0;
}
for (int i = 0; i < n; i++) {
pos[eq[i]]++;
}
cnt = 0;
for (int i = 0; i < n; i++) {
swap(cnt, pos[i]);
cnt += pos[i];
}
for (int i = 0; i < n; i++) {
int j = (perm[i] - (1 << k)) % n;
if (j < 0) {
j += n;
}
nxt_perm[pos[eq[j]]++] = j;
}
cnt = 0;
for (int i = 0; i < n; i++) {
pair_eq[i] = make_pair(eq[nxt_perm[i]], eq[(nxt_perm[i] + (1 << k)) % n]);
}
for (int i = 0; i < n; i++) {
if (i > 0 && pair_eq[i] != pair_eq[i - 1]) {
cnt++;
}
nxt_eq[nxt_perm[i]] = cnt;
}
swap(eq, nxt_eq);
swap(perm, nxt_perm);
}
for (int i = 0; i < n; i++) {
pos[perm[i]] = i;
}
int cur = 0;
for (int i = 0; i < n; i++) {
if (pos[i] == n - 1) {
continue;
}
int j = perm[pos[i] + 1];
while (i + cur < n && j + cur < n && a[i + cur] == a[j + cur]) {
cur++;
}
lcp[pos[i]] = cur;
if (cur > 0) {
cur--;
}
}
n--;
long long res = 0;
for (int k = 0; k < 2; k++) {
for (int i = 0; i <= n; i++) {
q_join[i].clear();
q_add[i].clear();
}
for (int i = 0; i < n; i++) {
q_add[pal[i * 2 + k] / 2].push_back(i);
}
for (int i = 0; i < n; i++) {
int u = perm[i];
int v = perm[i + 1];
q_join[lcp[i]].emplace_back(u, v);
}
int max_sz = 0;
for (int i = 0; i < n; i++) {
par[i] = -1;
depth[i] = 0;
sz[i] = 0;
}
for (int i = n; i >= 1; i--) {
for (auto u: q_add[i]) {
max_sz = max(max_sz, ++sz[root(u)]);
}
for (auto p: q_join[i]) {
int u = p.first;
int v = p.second;
update(u, v);
max_sz = max(max_sz, sz[root(u)]);
}
res = max(res, 1LL * (i * 2 - k) * max_sz);
}
}
cout << res;
}
// END MAIN CODE
