#include <bits/stdc++.h>
#define FOR(x, a, b) for (int x = a; x <= b; ++x)
#define FOD(x, a, b) for (int x = a; x >= b; --x)
#define REP(x, a, b) for (int x = a; x < b; ++x)
#define DEBUG(X) { cout << #X << " = " << X << endl; }
#define PR(A, n) { cout << #A << " = "; FOR(_, 1, n) cout << A[_] << " "; cout << endl; }
#define PR0(A, n) { cout << #A << " = "; REP(_, 0, n) cout << A[_] << " "; cout << endl; }
#define BitCount(x) __builtin_popcount(x)
using namespace std;
typedef long long LL;
const int N = 3e5 + 10;
int n;
char S[N];
struct PalindromeTree {
struct Node {
int l, r, Len, suffLink;
int nxt[26];
} T[N];
int TSize, suff;
void Init() {
TSize = suff = 2;
T[1].Len = -1; T[1].suffLink = 1;
T[2].Len = +0; T[2].suffLink = 1;
}
void AddLetter(int pos) {
int cur = suff;
int ltr = S[pos] - 'a';
while (true) {
int l = T[cur].Len;
if (pos - l - 1 >= 1 && S[pos - l - 1] == S[pos]) break;
cur = T[cur].suffLink;
}
if (T[cur].nxt[ltr]) {
suff = T[cur].nxt[ltr];
return;
}
suff = ++TSize;
T[TSize].Len = T[cur].Len + 2;
T[TSize].l = pos - T[TSize].Len + 1;
T[TSize].r = pos;
T[cur].nxt[ltr] = TSize;
if (T[TSize].Len == 1) {
T[TSize].suffLink = 2;
return;
}
while (true) {
cur = T[cur].suffLink;
int l = T[cur].Len;
if (pos - l - 1 >= 1 && S[pos - l - 1] == S[pos]) {
T[TSize].suffLink = T[cur].nxt[ltr];
break;
}
}
}
} PT;
struct SuffixArray {
int n;
int SA[N], LCP[N], num[N], L[N], R[N], C[N], pos[N];
char S[N];
bool mark[N];
void Init(string T) {
n = T.size() + 1;
FOR(i, 1, n - 1) S[i] = T[i - 1];
S[n] = 0;
BuildSA();
BuildLCP();
}
void BuildSA() {
memset(C, 0, sizeof C);
FOR(i, 1, n) C[S[i]]++;
FOR(i, 1, 255) C[i] += C[i - 1];
FOD(i, n, 1) R[C[S[i]]--] = i;
FOR(i, 2, n) mark[i] = S[R[i]] != S[R[i - 1]]; mark[1] = true;
for (int k = 1; k <= n; k <<= 1) {
int d = 0;
FOR(i, 1, n) {
if (mark[i]) ++d; num[R[i]] = d;
L[i] = (R[i] - k - 1 + 3 * n) % n + 1;
}
FOR(i, 0, n) C[i] = 0;
FOR(i, 1, n) C[num[L[i]]]++;
FOR(i, 1, n) C[i] += C[i - 1];
FOD(i, n, 1) R[C[num[L[i]]]--] = L[i];
int p = -1;
FOR(i, 1, n) {
int x = num[(R[i] + k - 1 + 3 * n) % n + 1];
mark[i] = p != x || num[R[i]] != num[R[i - 1]];
p = x;
}
}
n = n - 1;
FOR(i, 0, n) SA[i] = R[i + 1];
}
void BuildLCP() {
FOR(i, 1, n) pos[SA[i]] = i;
int x = 0; LCP[0] = 0;
FOR(i, 1, n) {
int j = SA[pos[i] - 1];
while (S[i + x] == S[j + x]) ++x;
LCP[pos[i]] = x;
x = max(x - 1, 0);
}
}
} SA;
struct RMQ {
static const int LG = 20;
int lg[N];
int spT[N][LG + 5];
void Init() {
FOR(i, 1, n) spT[i][0] = SA.LCP[i];
for (int j = 1; 1 << j <= n; ++j)
for (int i = 1; i + (1 << j) - 1 <= n; ++i)
spT[i][j] = min(spT[i][j - 1], spT[i + (1 << (j - 1))][j - 1]);
for (int i = 0; 1 << i <= n; ++i) lg[1 << i] = i;
FOR(i, 1, n) if (!lg[i]) lg[i] = lg[i - 1];
}
int LCP(int l, int r) {
int k = lg[r - l + 1];
return min(spT[l][k], spT[r - (1 << k) + 1][k]);
}
} RMQ;
int FindLeft(int i, int Len) {
int l = 1, r = i - 1, f = i;
while (l <= r) {
int m = (l + r) >> 1;
if (RMQ.LCP(m + 1, i) >= Len) {
f = m;
r = m - 1;
} else l = m + 1;
}
return f;
}
int FindRight(int i, int Len) {
int l = i + 1, r = n, f = i;
while (l <= r) {
int m = (l + r) >> 1;
if (RMQ.LCP(i + 1, m) >= Len) {
f = m;
l = m + 1;
} else r = m - 1;
}
return f;
}
int main() {
#ifdef LOCAL
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif // LOCAL
scanf("%s", S + 1); n = strlen(S + 1);
PT.Init();
FOR(i, 1, n) PT.AddLetter(i);
SA.Init(string(S + 1, S + n + 1));
RMQ.Init();
// PR(SA.SA, n);
// PR(SA.LCP, n);
LL ans = 0;
FOR(i, 3, PT.TSize) {
int k = PT.T[i].l, Length = PT.T[i].r - PT.T[i].l + 1;
int l = FindLeft(SA.pos[k], Length), r = FindRight(SA.pos[k], Length);
ans = max(ans, (LL)(r - l + 1) * Length);
}
printf("%lld", ans);
return 0;
}
