#include <bits/stdc++.h>

using namespace std;

const int N = 1e6 + 5;

int n;
string S;

struct Node {
    int nxt[26], link, len;
} p[N << 1];

int now, tot, ed[N];
long long f[N];

int insert(int x) {
    int k = ++tot;
    p[k].len = p[now].len + 1;
    while (~now && !p[now].nxt[x]) {
        p[now].nxt[x] = k;
        now = p[now].link;
    }
    if (!~now) {
        return now = k;
    }
    int t = p[now].nxt[x];
    if (p[now].len + 1 == p[t].len) p[k].link = t;
    else {
        int clone = ++tot;
        p[clone] = p[t];
        p[clone].len = p[now].len + 1;
        while (~now && p[now].nxt[x] == t) {
            p[now].nxt[x] = clone, now = p[now].link;
        }
        p[k].link = p[t].link = clone;
    }
    return now = k;
}

vector<int> T[N << 1];
int fa[20][N << 1], dfn[N << 1], siz[N << 1], dfn_cnt;

void dfs(int x) {
    fa[0][x] = max(p[x].link, 0);
    for (int i = 1; i < 20; ++i) fa[i][x] = fa[i - 1][fa[i - 1][x]];
    dfn[x] = ++dfn_cnt;
    siz[x] = 1;
    for (auto v : T[x]) dfs(v), siz[x] += siz[v];
}

int sum[N << 1];

void modify(int x) {
    for (; x <= dfn_cnt; x += x & -x) ++sum[x];
}

int query(int x) {
    int res = 0;
    for (; x; x -= x & -x) res += sum[x];
    return res;
}

int query(int l, int r) {
    return query(r) - query(l - 1);
}

int w(int l, int r) {
    int now = ed[r];
    for (int i = 19; ~i; --i) {
        if (fa[i][now] && p[fa[i][now]].len >= r - l + 1) now = fa[i][now];
    }
    return query(dfn[now], dfn[now] + siz[now] - 1);
}

void upd(int y, int x) {
    f[x] = max(f[x], w(y + 1, x) - f[y]);
}

int stk[N];

signed main() {
    cin >> S, n = S.size();
    reverse(S.begin(), S.end()), S = " " + S;
    p[0].link = -1;
    for (int i = 1; i <= n; ++i) {
        ed[i] = insert(S[i] - 'a');
    }
    for (int i = 1; i <= tot; ++i) T[p[i].link].push_back(i);
    dfs(0);
    stk[++stk[0]] = 0;
    for (int i = 1; i <= n; ++i) {
        modify(dfn[ed[i]]);
        f[i] = -1e18, upd(stk[stk[0]], i);
        while (stk[0] && f[i] <= f[stk[stk[0]]]) {
            --stk[0];
            if (stk[0]) upd(stk[stk[0]], i);
        }
        stk[++stk[0]] = i;
    }
    printf("%lld\n", f[n]);
    return 0;
}