#include<bits/stdc++.h>
#define ll long long
#define ld long double
#define i1 __int128
#define pii pair<int, int>
#define pll pair<ll, ll>
#define mp make_pair
#define mt make_tuple
#define fi first
#define se second
#define ep emplace
#define eb emplace_back
#define all(v) v.begin(), v.end()

using namespace std;

template<typename types>
void read(types &x) {
    x = 0; char c = getchar(); int f = 1;
    while (!isdigit(c)) { if (c == '-') f = -1; c = getchar(); }
    while (isdigit(c)) x = x * 10 + c - '0', c = getchar();
    x *= f; return;
}
void read() {}
template<typename types, typename... Args>
void read(types &x, Args&... args) {
    read(x), read(args...);
    return;
}
template<typename types>
void write(types x) {
    if (x < 0) putchar('-'), x = -x;
    types k = x / 10;
    if (k) write(k);
    putchar(x - k * 10 + '0');
    return;
}
void print() { puts(""); }
template<typename types, typename... Args>
void print(types x, Args... args) {
    write(x), putchar(' '), print(args...);
    return;
}

const int MAXN = 4e5 + 10;
const int AL = 26;

struct Node {
    int link, cnt, len;
    int ch[AL];
} a[MAXN];
vector<int> buc[MAXN];
int idx, last;

void extend(int x) {
    int now = ++idx;
    int p = last; last = now;
    a[now].len = a[p].len + 1;
    while (~p && !a[p].ch[x]) a[p].ch[x] = now, p = a[p].link;
    if (p == -1) a[now].link = 0;
    else {
        int q = a[p].ch[x];
        if (a[q].len == a[p].len + 1) a[now].link = q;
        else {
            int cl = ++idx; a[cl] = a[q];
            a[cl].len = a[p].len + 1;
            a[now].link = a[q].link = cl;
            while (~p && a[p].ch[x] == q) a[p].ch[x] = cl, p = a[p].link;
        }
    }
    last = now;
    return;
}

int main() {
    ios:: sync_with_stdio(false);
    cin.tie(0), cout.tie(0);
    a[0].link = -1;
    string s; cin >> s;
    for (char c : s) extend(c - 'a');
    int p = 0;
    for (char c : s) p = a[p].ch[c - 'a'], ++a[p].cnt;
    for (int i = 1; i <= idx; ++i) buc[a[i].len].eb(i);
    ll ans = 0;
    for (int l = s.length(); l; --l) 
        for (int i : buc[l]) {
            a[a[i].link].cnt += a[i].cnt;
            if (a[i].cnt > 1) ans = max(ans, (ll) a[i].len * a[i].cnt);
        }
    cout << ans << endl;
    return 0;
}