#include <bits/stdc++.h>

using namespace std;

#define REP(i, n) for (int i=0; i<(n); ++i)
#define FOR(i, a, n) for (int i=(a); i<(n); ++i)

#define SZ(x) ((int)(x).size())
#define ALL(x) (x).begin(),(x).end()

#define DUMP(x) cerr<<#x<<" = "<<(x)<<endl
#define DEBUG(x) cerr<<#x<<" = "<<(x)<<" (L"<<__LINE__<<")"<<endl;

template<class T>
ostream &operator<<(ostream &os, const vector<T> &v) {
  os << "[";
  REP(i, SZ(v)) {
    if (i) os << ", ";
    os << v[i];
  }
  return os << "]";
}

template<class T, class U>
ostream &operator<<(ostream &os, const pair<T, U> &p) {
  return os << "(" << p.first << " " << p.second << ")";
}

template<class T>
bool chmax(T &a, const T &b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}

template<class T>
bool chmin(T &a, const T &b) {
  if (b < a) {
    a = b;
    return true;
  }
  return false;
}

using ll = long long;
using ull = unsigned long long;
using ld = long double;
using P = pair<int, int>;
using vi = vector<int>;
using vll = vector<ll>;
using vvi = vector<vi>;
using vvll = vector<vll>;

const ll MOD = 1e9 + 7;
const int INF = INT_MAX / 2;
const ll LINF = LLONG_MAX / 2;
const ld eps = 1e-9;

struct Triangle {
  vi v = {0, 1, 2};
  P now = {0, 0};
  int dir = 1; // 1: up, 0: down

  void flip0() {
    vi u = v;
    v[0] = u[2];
    v[1] = u[0];
    v[2] = u[1];
    dir = !dir;
    now.second--;
  };

  void flip1() {
    vi u = v;
    v[0] = u[1];
    v[1] = u[2];
    v[2] = u[0];
    dir = !dir;
    now.second++;
  };

  void flip2() {
    dir = !dir;
    if((now.first + now.second) % 2) {
      now.first++;
    } else {
      now.first--;
    }
  }

};

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  cout << fixed << setprecision(10);

  string s;
  cin >> s;
  int n = SZ(s);
  set<P> st;
  Triangle t;
  st.insert(t.now);
  REP(i, n) {
    if(s[i] == 'a') {
      if(t.v[0] == 0) {
        t.flip0();
      } else if(t.v[1] == 0) {
        t.flip1();
      } else {
        t.flip2();
      }
    } else if(s[i] == 'b') {
      if(t.v[0] == 1) {
        t.flip0();
      } else if(t.v[1] == 1) {
        t.flip1();
      } else {
        t.flip2();
      }
    } else {
      if(t.v[0] == 2) {
        t.flip0();
      } else if(t.v[1] == 2) {
        t.flip1();
      } else {
        t.flip2();
      }
    }
    st.insert(t.now);
  }

  cout << SZ(st) << endl;


  return 0;
}