#include <bits/stdc++.h>
using namespace std;
using ll = int64_t;
class CerrDummy {
} cerrDummy;
template <class T>
CerrDummy& operator<<(CerrDummy& cd, const T&) {
  return cd;
}
using charTDummy = char;
using traitsDummy = char_traits<charTDummy>;
CerrDummy& operator<<(CerrDummy& cd,
                      basic_ostream<charTDummy, traitsDummy>&(
                          basic_ostream<charTDummy, traitsDummy>&)) {
  return cd;
}
using pi = pair<ll, ll>;
using vi = vector<ll>;
using ld = long double;
template <class T, class U>
ostream& operator<<(ostream& os, const pair<T, U>& p) {
  os << "(" << p.first << "," << p.second << ")";
  return os;
}
template <class T>
ostream& operator<<(ostream& os, const vector<T>& v) {
  os << "{";
  for (ll i = ll(0); i < ll((ll)v.size()); i++) {
    if (i) os << ",";
    os << v[i];
  }
  os << "}";
  return os;
}
ll read() {
  ll i;
  scanf("%" SCNd64, &i);
  return i;
}
void printSpace() { printf(" "); }
void printEoln() { printf("\n"); }
void print(ll x, ll suc = 1) {
  printf("%" PRId64, x);
  if (suc == 1) printEoln();
  if (suc == 2) printSpace();
}
string readString() {
  static char buf[3341000];
  scanf("%s", buf);
  return string(buf);
}
char* readCharArray() {
  static char buf[3341000];
  static ll bufUsed = 0;
  char* ret = buf + bufUsed;
  scanf("%s", ret);
  bufUsed += strlen(ret) + 1;
  return ret;
}
template <class T, class U>
void chmax(T& a, U b) {
  if (a < b) a = b;
}
template <class T, class U>
void chmin(T& a, U b) {
  if (b < a) a = b;
}
template <class T>
T Sq(const T& t) {
  return t * t;
}
void Yes(bool ex = true) {
  cout << "YES" << endl;
  if (ex) exit(0);
}
void No(bool ex = true) {
  cout << "NO" << endl;
  if (ex) exit(0);
}
const ll infLL = LLONG_MAX / 3;
const ll inf = infLL;
const ll mod = 1000000007;
template <class T, class U>
void add(T& a, U b) {
  a += b;
  if (a >= mod) a -= mod;
}
template <class T, class U>
void sub(T& a, U b) {
  a -= b;
  if (a < 0) a += mod;
}
template <class T, class U>
void mult(T& a, U b) {
  a = ((ll)a * b) % mod;
}
ll modPow(ll a, ll p) {
  ll s = 1;
  while (p) {
    if (p & 1) mult(s, a);
    mult(a, a);
    p >>= 1;
  }
  return s;
}
ll modInv(ll a) { return modPow(a, mod - 2); }
const ll Vmax = 1000010;
ll fact[Vmax], factInv[Vmax];
void InitFact() {
  fact[0] = 1;
  for (ll i = ll(1); i < ll(Vmax); i++) {
    fact[i] = fact[i - 1];
    mult(fact[i], i);
  }
  factInv[Vmax - 1] = modInv(fact[Vmax - 1]);
  for (ll i = Vmax - 2; i >= 0; i--) {
    factInv[i] = factInv[i + 1];
    mult(factInv[i], i + 1);
  }
}
ll Choose(ll n, ll k) {
  return ll(fact[n]) * factInv[n - k] % mod * factInv[k] % mod;
}
ll Binom(ll a, ll b) {
  return ll(fact[a + b]) * factInv[a] % mod * factInv[b] % mod;
}
vi Waf(string s) {
  ll n = s.size();
  vi res(n, 0);
  res[n - 1] = 1;
  for (ll i = n - 2; i >= 0; i--)
    if (s[i] == s[i + 1]) {
      for (ll j = ll(0); j < ll(i + 1); j++) res[j] = 1;
    }
  cerrDummy << res << endl;
  return res;
}
signed main() {
  string s = readString();
  ll n = s.size();
  vi sum(n + 1, 0);
  for (ll i = ll(0); i < ll(n); i++) {
    ll c = s[i] == 'a' ? 1 : 2;
    sum[i + 1] = (sum[i] + c) % 3;
  }
  cerrDummy << endl;
  vector<vi> to(n + 1, vi(3, 0));
  ll last[3] = {-1, -1, -1};
  for (ll i = n; i >= 0; i--) {
    for (ll k = ll(0); k < ll(3); k++) to[i][k] = last[(sum[i] + k) % 3];
    last[sum[i]] = i;
  }
  cerrDummy << to << endl;
  cerrDummy << endl;
  vi use = Waf(s);
  ll ans = 0;
  vi dp(n + 1, 0);
  dp[0] = 1;
  for (ll i = ll(0); i < ll(n); i++) {
    if (use[i] && sum[i] != sum[n]) {
      cerrDummy << i << " " << dp[i] << endl;
      add(ans, dp[i]);
    }
    for (ll k = ll(1); k < ll(3); k++)
      if (to[i][k] != -1) {
        cerrDummy << i << "->" << to[i][k] << endl;
        add(dp[to[i][k]], dp[i]);
        if (to[i][k] < n && use[i] && !use[to[i][k]] &&
            sum[to[i][k]] != sum[n]) {
          add(ans, dp[i]);
        }
      }
  }
  cerrDummy << dp << endl;
  print(ans);
}
