#include <cassert>
#include <cmath>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <functional>
#include <iostream>
#include <limits>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

using namespace std;

using Int = long long;

template <class T1, class T2> ostream &operator<<(ostream &os, const pair<T1, T2> &a) { return os << "(" << a.first << ", " << a.second << ")"; };
template <class T> ostream &operator<<(ostream &os, const vector<T> &as) { const int sz = as.size(); os << "["; for (int i = 0; i < sz; ++i) { if (i >= 256) { os << ", ..."; break; } if (i > 0) { os << ", "; } os << as[i]; } return os << "]"; }
template <class T> void pv(T a, T b) { for (T i = a; i != b; ++i) cerr << *i << " "; cerr << endl; }
template <class T> bool chmin(T &t, const T &f) { if (t > f) { t = f; return true; } return false; }
template <class T> bool chmax(T &t, const T &f) { if (t < f) { t = f; return true; } return false; }
#define COLOR(s) ("\x1b[" s "m")

////////////////////////////////////////////////////////////////////////////////
// SA-IS
//   String: string, vector<int>, vector<long long>
//   if sigma <= n,  O(n) time, O(n) space
//   if sigma >  n,  O(n log n) time, O(n) space
template <class String> vector<int> suffixArrayRec(const String &as) {
  const int n = as.size();
  if (n == 0) return {};
  const auto minmaxA = minmax_element(as.begin(), as.end());
  const auto minA = *minmaxA.first, maxA = *minmaxA.second;
  if (static_cast<unsigned long long>(maxA) - minA >=
      static_cast<unsigned long long>(n)) {
    vector<int> us(n);
    for (int u = 0; u < n; ++u) us[u] = u;
    std::sort(us.begin(), us.end(), [&](int u, int v) -> bool {
      return (as[u] < as[v]);
    });
    int b = 0;
    vector<int> bs(n, 0);
    for (int i = 1; i < n; ++i) {
      if (as[us[i - 1]] != as[us[i]]) ++b;
      bs[us[i]] = b;
    }
    return suffixArrayRec(bs);
  }
  const int sigma = maxA - minA + 1;
  vector<int> pt(sigma + 1, 0), poss(sigma);
  for (int u = 0; u < n; ++u) ++pt[as[u] - minA + 1];
  for (int a = 0; a < sigma; ++a) pt[a + 1] += pt[a];
  // cmp[u] := (as[u, n) < as[u + 1, n))
  vector<bool> cmp(n);
  cmp[n - 1] = false;
  for (int u = n - 1; --u >= 0; ) {
    cmp[u] = (as[u] != as[u + 1]) ? (as[u] < as[u + 1]) : cmp[u + 1];
  }
  // ><,  nn - id (0 <= id < n)
  int nn = 0;
  vector<int> ids(n, 0);
  int last = n;
  vector<int> nxt(n, 0);
  // put ><, from the tail of each bucket
  vector<int> us(n, 0);
  memcpy(poss.data(), pt.data() + 1, sigma * sizeof(int));
  for (int u = n - 1; --u >= 1; ) if (!cmp[u - 1] && cmp[u]) {
    ids[u] = ++nn;
    nxt[u] = last;
    last = u;
    us[--poss[as[u] - minA]] = u;
  }
  // follow > backwards, from the head of each bucket
  memcpy(poss.data(), pt.data(), sigma * sizeof(int));
  us[poss[as[n - 1] - minA]++] = n - 1;
  for (int i = 0; i < n; ++i) {
    const int u = us[i];
    if (u && !cmp[u - 1]) us[poss[as[u - 1] - minA]++] = u - 1;
  }
  // follow < backwards, from the tail of each bucket
  memcpy(poss.data(), pt.data() + 1, sigma * sizeof(int));
  for (int i = n; --i >= 0; ) {
    const int u = us[i];
    if (u && cmp[u - 1]) us[--poss[as[u - 1] - minA]] = u - 1;
  }
  if (nn) {
    int vsLen = 0;
    vector<int> vs(nn);
    for (const int u : us) if (ids[u]) vs[vsLen++] = u;
    int b = 0;
    vector<int> bs(nn, 0);
    for (int j = 1; j < nn; ++j) {
      // as[v1, w1] (< or =) as[v0, w0]
      int v1 = vs[j - 1], v0 = vs[j];
      const int w1 = nxt[v1], w0 = nxt[v0];
      if (w1 - v1 != w0 - v0) {
        ++b;
      } else {
        for (; ; ++v1, ++v0) {
          if (v1 == n) { ++b; break; }
          if (as[v1] != as[v0]) { ++b; break; }
          if (v1 == w1) break;
        }
      }
      bs[nn - ids[vs[j]]] = b;
    }
    for (int u = 0; u < n; ++u) if (ids[u]) vs[nn - ids[u]] = u;
    const auto sub = suffixArrayRec(bs);
    // put ><, from the tail of each bucket
    memset(us.data(), 0, n * sizeof(int));
    memcpy(poss.data(), pt.data() + 1, sigma * sizeof(int));
    for (int j = nn; --j >= 0; ) {
      const int u = vs[sub[j]];
      us[--poss[as[u] - minA]] = u;
    }
    // follow > backwards, from the head of each bucket
    memcpy(poss.data(), pt.data(), sigma * sizeof(int));
    us[poss[as[n - 1] - minA]++] = n - 1;
    for (int i = 0; i < n; ++i) {
      const int u = us[i];
      if (u && !cmp[u - 1]) us[poss[as[u - 1] - minA]++] = u - 1;
    }
    // follow < backwards, from the tail of each bucket
    memcpy(poss.data(), pt.data() + 1, sigma * sizeof(int));
    for (int i = n; --i >= 0; ) {
      const int u = us[i];
      if (u && cmp[u - 1]) us[--poss[as[u - 1] - minA]] = u - 1;
    }
  }
  return us;
}

// us[i]: i-th suffix
// su[u]: index of as[u, n)
// hs[i]: longest common prefix of as[us[i - 1], n) and as[us[i], n)
struct SuffixArray {
  int n;
  bool rmq;
  vector<int> us, su, hs;
  SuffixArray() : n(0), rmq(false) {}
  SuffixArray(const string &as, bool rmq_) : rmq(rmq_) { build(as); }
  SuffixArray(const vector<int> &as, bool rmq_) : rmq(rmq_) { build(as); }
  SuffixArray(const vector<long long> &as, bool rmq_) : rmq(rmq_) { build(as); }
  template <class String> void build(const String &as) {
    n = as.size();
    us = suffixArrayRec(as);
    su.resize(n + 1);
    for (int i = 0; i < n; ++i) su[us[i]] = i;
    su[n] = -1;
    hs.assign(n, 0);
    for (int h = 0, u = 0; u < n; ++u) if (su[u]) {
      for (int v = us[su[u] - 1]; v + h < n && as[v + h] == as[u + h]; ++h) {}
      hs[su[u]] = h;
      if (h) --h;
    }
    if (rmq) {
      const int logN = n ? (31 - __builtin_clz(n)) : 0;
      hs.resize((logN + 1) * n - (1 << logN) + 1);
      for (int e = 0; e < logN; ++e) {
        int *hes = hs.data() + e * n;
        for (int i = 0; i <= n - (1 << (e + 1)); ++i) {
          hes[n + i] = min(hes[i], hes[i + (1 << e)]);
        }
      }
    }
  }
  // Returns longest common prefix of as[u, n) and as[v, n).
  //   0 <= u, v <= n
  //   Assumes rmq.
  inline int lcp(int u, int v) const {
    if (u == v) return n - u;
    int i = su[u], j = su[v];
    if (i > j) swap(i, j);
    const int e = 31 - __builtin_clz(j - i);
    return min(hs[e * n + i + 1], hs[e * n + j + 1 - (1 << e)]);
  }
};
////////////////////////////////////////////////////////////////////////////////


// T: monoid representing information of an interval.
//   T()  should return the identity.
//   T(S s)  should represent a single element of the array.
//   T::pull(const T &l, const T &r)  should pull two intervals.
template <class T> struct SegmentTreePoint {
  int logN, n;
  vector<T> ts;
  SegmentTreePoint() : logN(0), n(0) {}
  explicit SegmentTreePoint(int n_) {
    for (logN = 0, n = 1; n < n_; ++logN, n <<= 1) {}
    ts.resize(n << 1);
  }
  template <class S> explicit SegmentTreePoint(const vector<S> &ss) {
    const int n_ = ss.size();
    for (logN = 0, n = 1; n < n_; ++logN, n <<= 1) {}
    ts.resize(n << 1);
    for (int i = 0; i < n_; ++i) at(i) = T(ss[i]);
    build();
  }
  T &at(int i) {
    return ts[n + i];
  }
  void build() {
    for (int u = n; --u; ) pull(u);
  }

  inline void pull(int u) {
    ts[u].pull(ts[u << 1], ts[u << 1 | 1]);
  }

  // Changes the value of point a to s.
  template <class S> void change(int a, const S &s) {
    assert(0 <= a); assert(a < n);
    ts[a += n] = T(s);
    for (; a >>= 1; ) pull(a);
  }

  // Applies T::f(args...) to point a.
  template <class F, class... Args>
  void ch(int a, F f, Args &&... args) {
    assert(0 <= a); assert(a < n);
    (ts[a += n].*f)(args...);
    for (; a >>= 1; ) pull(a);
  }

  // Calculates the product for [a, b).
  T get(int a, int b) {
    assert(0 <= a); assert(a <= b); assert(b <= n);
    if (a == b) return T();
    T prodL, prodR, t;
    for (a += n, b += n; a < b; a >>= 1, b >>= 1) {
      if (a & 1) { t.pull(prodL, ts[a++]); prodL = t; }
      if (b & 1) { t.pull(ts[--b], prodR); prodR = t; }
    }
    t.pull(prodL, prodR);
    return t;
  }

  // Calculates T::f(args...) of a monoid type for [a, b).
  //   op(-, -)  should calculate the product.
  //   e()  should return the identity.
  template <class Op, class E, class F, class... Args>
#if __cplusplus >= 201402L
  auto
#else
  decltype((std::declval<T>().*F())())
#endif
  get(int a, int b, Op op, E e, F f, Args &&... args) {
    assert(0 <= a); assert(a <= b); assert(b <= n);
    if (a == b) return e();
    auto prodL = e(), prodR = e();
    for (a += n, b += n; a < b; a >>= 1, b >>= 1) {
      if (a & 1) prodL = op(prodL, (ts[a++].*f)(args...));
      if (b & 1) prodR = op((ts[--b].*f)(args...), prodR);
    }
    return op(prodL, prodR);
  }

  // Find min b s.t. T::f(args...) returns true,
  // when called for the partition of [a, b) from left to right.
  //   Returns n + 1 if there is no such b.
  template <class F, class... Args>
  int findRight(int a, F f, Args &&... args) {
    assert(0 <= a); assert(a <= n);
    if ((T().*f)(args...)) return a;
    if (a == n) return n + 1;
    a += n;
    for (; ; a >>= 1) if (a & 1) {
      if ((ts[a].*f)(args...)) {
        for (; a < n; ) {
          if (!(ts[a <<= 1].*f)(args...)) ++a;
        }
        return a - n + 1;
      }
      ++a;
      if (!(a & (a - 1))) return n + 1;
    }
  }

  // Find max a s.t. T::f(args...) returns true,
  // when called for the partition of [a, b) from right to left.
  //   Returns -1 if there is no such a.
  template <class F, class... Args>
  int findLeft(int b, F f, Args &&... args) {
    assert(0 <= b); assert(b <= n);
    if ((T().*f)(args...)) return b;
    if (b == 0) return -1;
    b += n;
    for (; ; b >>= 1) if ((b & 1) || b == 2) {
      if ((ts[b - 1].*f)(args...)) {
        for (; b <= n; ) {
          if (!(ts[(b <<= 1) - 1].*f)(args...)) --b;
        }
        return b - n - 1;
      }
      --b;
      if (!(b & (b - 1))) return -1;
    }
  }
};  // SegmentTreePoint<T>

////////////////////////////////////////////////////////////////////////////////

constexpr int INF = 1001001001;

struct NodeMin {
  int mn;
  NodeMin() : mn(+INF) {}
  NodeMin(int val) : mn(val) {}
  void pull(const NodeMin &l, const NodeMin &r) {
    mn = min(l.mn, r.mn);
  }
  void ch(int val) {
    mn = val;
  }
  void chmin(int val) {
    if (mn > val) mn = val;
  }
  bool test(int tar) const {
    return (mn <= tar);
  }
};


template <class T> void bAdd(vector<T> &bit, int pos, const T &val) {
  const int bitN = bit.size();
  for (int x = pos; x < bitN; x |= x + 1) bit[x] += val;
}
template <class T> T bSum(const vector<T> &bit, int pos) {
  T ret = 0;
  for (int x = pos; x > 0; x &= x - 1) ret += bit[x - 1];
  return ret;
}
template <class T> T bSum(const vector<T> &bit, int pos0, int pos1) {
  return bSum(bit, pos1) - bSum(bit, pos0);
}


/*
  occ[l, r) := (# occurrence of S[l, r) in S[l, N))
  dp[N] = 0
  dp[l] = \max[l<r<=N] (occ[l, r) - dp[r])
  
  l+1 <= r < r' <= N
  ==> occ[l, r) >= occ[l, r')
  if dp[r] <= dp[r'], then r' is useless
  keep prefix min
  
  stack: l+1 <= r[0] < r[1] < ...
  f[j] := occ[l, r[j]) - dp[r[j]]
  dp[l] = max{ f[0],...,f[j], \max[r[j]<r<=N] (occ[l, r) - dp[r]) }
       <= max{ f[0],...,f[j], \max[r[j]<r<=N] (occ[r[j], r) - dp[r]) }
       <= max{ f[0],...,f[j], dp[r[j]] }
  
  Case. max{ f[0],...,f[j] } > dp[r[j]]
    dp[l] = max{ f[0],...,f[j] }
    determined
    push l
  Case. max{ f[0],...,f[j] } <= dp[r[j]]
    dp[l] <= dp[r[j]]
    pop r[j]
*/

int N;
char S[1'000'010];

SuffixArray sa;
SegmentTreePoint<NodeMin> seg;
vector<int> bit;

void add(int l) {
  bAdd(bit, sa.su[l], +1);
}
int occ(int l, int r) {
  const int pos = sa.su[l];
  // hs[i]: longest common prefix of as[us[i - 1], n) and as[us[i], n)
  // LCP(posL - 1, posL), LCP(posR, posR + 1) are too small
  const int posL = max(seg.findLeft(pos + 1, &NodeMin::test, (r-l) - 1), 0);
  const int posR = min(seg.findRight(pos + 1, &NodeMin::test, (r-l) - 1) - 2, N - 1);
  const int ret = bSum(bit, posL, posR + 1);
// cerr<<"[occ] "<<l<<" "<<r<<": "<<posL<<" "<<pos<<" "<<posR<<"; "<<ret<<endl;
  return ret;
}

int main() {
  for (; ~scanf("%s", S); ) {
    N = strlen(S);
    
    sa.build(string(S));
// for(int i=0;i<N;++i)cerr<<(S+sa.us[i])<<endl;
// cerr<<"hs = "<<sa.hs<<endl;
    seg = SegmentTreePoint<NodeMin>(sa.hs);
    bit.assign(N, 0);
    
    vector<int> dp(N + 1, 0);
    vector<int> stack{N};
    for (int l = N; --l >= 0; ) {
      add(l);
      for (; stack.size(); ) {
        const int r = stack.back();
        chmax(dp[l], occ(l, r) - dp[r]);
        if (dp[l] > dp[r]) {
          break;
        } else {
          stack.pop_back();
        }
      }
      stack.push_back(l);
    }
    printf("%d\n", dp[0]);
    
#ifdef LOCAL
vector<int>brt(N+1,-1001001001);
brt[N]=0;
for(int l=N;--l>=0;)for(int r=l+1;r<=N;++r){
 int cnt=0;
 for(int i=l;i+(r-l)<=N;++i)if(string(S+l,S+r)==string(S+i,S+(i+(r-l))))++cnt;
 chmax(brt[l],cnt-brt[r]);
}
cerr<<"brt = "<<brt<<endl;
cerr<<"dp  = "<<dp <<endl;
assert(brt==dp);
#endif
  }
  return 0;
}