#include <bits/stdc++.h>
#define pb push_back
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define f first
#define s second
using namespace std;
using ll = long long;
using pii = pair <int, int>;
using vi = vector <int>;
const int N = 3e5 + 5, base[] = {301991, 400457}, mod[] = {(int)1e9 + 7, 998244353};
int n, pw[N][2], len[N], cnt[N];
ll ans;
bool used[N];
pii h[N];
vector <int> g[N];
string s;
pii get(int l, int r) {
if (l > r)
return {0, 0};
if (!l)
return h[r];
int f = h[r].f - (h[l - 1].f * 1ll * pw[r - l + 1][0] % mod[0]);
if (f < 0) f += mod[0];
int se = h[r].s - (h[l - 1].s * 1ll * pw[r - l + 1][1] % mod[1]);
if (se < 0) se += mod[1];
return {f, se};
}
void dfs(int v) {
used[v] = 1;
for (auto to : g[v]) {
if (used[to])
continue;
dfs(to);
cnt[v] += cnt[to];
}
/*cout << v << ' ' << len[v] << ' ' << cnt[v] << '\n';
cout << "sons\n";
for (auto to : g[v]) {
cout << to << ' ';
}
cout << '\n';*/
ans = max(ans, 1ll * cnt[v] * len[v]);
}
int main() {
ios :: sync_with_stdio(0);
cin.tie(0);
cin >> s;
n = sz(s);
h[0].f = s[0];
h[0].s = s[0];
pw[0][0] = pw[0][1] = 1;
for (int i = 1; i <= n; ++i) {
if (i < n) {
h[i].f = (h[i - 1].f * 1ll * base[0] + s[i]) % mod[0];
h[i].s = (h[i - 1].s * 1ll * base[1] + s[i]) % mod[1];
}
pw[i][0] = pw[i - 1][0] * 1ll * base[0] % mod[0];
pw[i][1] = pw[i - 1][1] * 1ll * base[1] % mod[1];
}
map <pii, int> ind;
ind[{0, 0}] = 0;
int sz = 0;
array <vi, 2> p = {vi(n + 1), vi(n)};
for (int z = 0; z < 2; ++z) {
for (int i = 0, l = 0, r = 0; i < n; ++i) {
int t = r - i + !z;
if (i < r)
p[z][i] = min(t, p[z][l + t]);
int L = i - p[z][i], R = i + p[z][i] - !z;
pii cur = get(L, R);
if (!ind.count(cur)) {
ind[cur] = ++sz;
len[ind[cur]] = R - L + 1;
}
if (L == R)
g[0].pb(ind[cur]);
while (L >= 1 && R + 1 < n && s[L - 1] == s[R + 1]) {
p[z][i]++, L--, R++;
pii prv = cur;
cur = get(L, R);
if (!ind.count(cur)) {
ind[cur] = ++sz;
len[ind[cur]] = R - L + 1;
}
//cout << "wtf " << ind[prv] << ' ' << ind[cur] << '\n';
g[ind[prv]].pb(ind[cur]);
}
cnt[ind[cur]]++;
if (R > r) l = L, r = R;
}
}
dfs(0);
cout << ans;
return 0;
}
