#include <bits/stdc++.h>
using namespace std;
const int N = 300'000 + 10;
string s;
int n;
struct Hash {
int base, M;
vector<int> h, rh, pw;
Hash() : base(0), M(0) {}
Hash(string s, int base, int M) : base(base), M(M), h(s.size() + 1), rh(s.size() + 1), pw(s.size() + 1) {
pw[0] = 1;
for (int i = 1; i <= n; ++i) {
pw[i] = 1ll * pw[i - 1] * base % M;
h[i] = (1ll * h[i - 1] * base % M + s[i - 1]) % M;
rh[i] = (1ll * rh[i - 1] * base % M + s[n - i]) % M;
}
}
int get(int l, int r) {
return (h[r] - 1ll * h[l - 1] * pw[r - l + 1] % M + M) % M;
}
int rget(int l, int r) {
return (rh[r] - 1ll * rh[l - 1] * pw[r - l + 1] % M + M) % M;
}
} T[2];
using HASH = pair<int, int>;
inline HASH get(int l, int r) {
return make_pair(T[0].get(l, r), T[1].get(l, r));
}
inline HASH rget(int l, int r) {
tie(l, r) = make_pair(n - r + 1, n - l + 1);
return make_pair(T[0].rget(l, r), T[1].rget(l, r));
}
inline bool chk(int l, int r) { return get(l, r) == rget(l, r); }
int pos[N], tmp[N], sa[N];
int lcp[N];
void initSA() {
for (int i = 1; i <= n; ++i) pos[i] = s[i] - 'a' + 1, sa[i] = i;
for (int gap = 1; ; gap *= 2) {
auto cmp = [&](int i, int j) {
if (pos[i] != pos[j]) return pos[i] < pos[j];
i += gap; j += gap;
return i <= n && j <= n ? pos[i] < pos[j] : i > j;
};
sort(sa + 1, sa + n + 1, cmp);
for (int i = 2; i <= n; ++i) tmp[i] = tmp[i - 1] + cmp(sa[i - 1], sa[i]);
for (int i = 1; i <= n; ++i) pos[sa[i]] = tmp[i] + 1;
if (tmp[n] == n - 1) break;
}
for (int i = 1, k = 0; i <= n; ++i) {
if (pos[i] == n) continue;
for (int j = sa[pos[i] + 1]; s[i + k] == s[j + k]; ) k += 1;
lcp[i] = k;
if (k) k -= 1;
}
}
int f[N][19], lg[N];
void init() {
for (int i = 2; i <= n; ++i) lg[i] = lg[i >> 1] + 1;
for (int i = 1; i <= n; ++i) f[i][0] = lcp[sa[i]];
for (int j = 1; j <= 18; ++j) {
for (int i = 1; i <= n - (1 << j) + 1; ++i)
f[i][j] = min(f[i][j - 1], f[i + (1 << j - 1)][j - 1]);
}
}
inline int que(int l, int r) {
int j = lg[r - l + 1];
return min(f[l][j], f[r - (1 << j) + 1][j]);
}
int32_t main() {
cin.tie(0)->sync_with_stdio(0);
cin >> s;
n = s.size();
T[0] = Hash(s, 19937, 1e9 + 7);
T[1] = Hash(s, 10007, 1e9 + 9);
s = '@' + s;
initSA();
init();
auto count = [&](int l, int r) {
int sz = r - l + 1;
l = pos[l];
int value = 0;
{ // binarySearch left
int le = 1, ri = l - 1, ret = l;
while (le <= ri) {
int mid = (le + ri) >> 1;
if (que(mid, l - 1) >= sz) ri = (ret = mid) - 1;
else le = mid + 1;
}
value -= ret - 1;
}
{ //binarySearch right
int le = l, ri = n - 1, ret = l;
while (le <= ri) {
int mid = (le + ri) >> 1;
if (que(l, mid) >= sz) le = ret = mid + 1;
else ri = mid - 1;
}
value += ret;
}
return value;
};
long long answer = 0;
for (int mid1 = 1; mid1 <= n; ++mid1) {
for (int mid2 = mid1; mid2 <= min(n, mid1 + 1); ++mid2) {
if (!chk(mid1, mid2)) continue;
int sz = min(mid1, n - mid2);
int l = 0, r = sz, ret = 0;
while (l <= r) {
int mid = (l + r) >> 1;
if (chk(mid1 - mid, mid2 + mid)) l = (ret = mid) + 1;
else r = mid - 1;
}
answer = max(answer, 1ll * count(mid1 - ret, mid2 + ret) * (mid2 - mid1 + 2 * ret + 1));
}
}
cout << answer << "\n";
}
