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#include <unordered_map>
#include <vector>
#include <cstring>
#include <cstdio>

#define ll long long

const ll BASE = 1 << 26;

using namespace std;

class PrevDiffs {
  unordered_map<ll, int> cmap;
  ll res = 0;

public:
  PrevDiffs(ll zero) {
    cmap[zero] = 1;
  }

  ll getRes() {
    return res;
  }

  void update(ll x) {
    auto it = cmap.find(x);
    if(it != cmap.end()) {
      res += it->second;
      cmap[x] = (it->second) + 1;
    } else {
      cmap[x] = 1;
    }
  }
};

class Solver {
  char* a;
  int n;

public:
  Solver(char* a, int n): a(a), n(n) {}

  ll solve() {
    ll res = 0;
    res += countSingleLetter();
    res += countTwoLetters();
    res += countThreeLetters();
    return res;
  }

private:
  ll countSingleLetter() {
    ll res = 0;
    ll start = 0;
    for(int i=0;i<=n;i++) {
      if((i == n) || ((i > 0) && (a[i] != a[i-1]))) {
        res += ((i - start) * (i - start + 1)) / 2;
        start = i;
      }
    }
    return res;
  }

  ll countTwoLetters() {
    ll res = 0;
    vector<int> start(3, -1);
    vector<int> last(3, -1);
    int cnt[n+1][3];
    fill(cnt[0], cnt[0] + 3, 0);
    vector<int> biggest(2, -1);
    vector<int> nbiggest(2, -1);
    PrevDiffs* pd = new PrevDiffs(0);
    int c = 0;
    int base = 0;
    for(int i=0;i<n;i++) {
      int r = a[i] - 'a';
      if((i == 0) || (a[i] != a[i-1])) {
        start[r] = i;
      }
      last[r] = i;
      memcpy(cnt[i+1], cnt[i], sizeof(int) * 3);
      cnt[i+1][r]++;
      if(c < 3) {
        c = 0;
        for(auto &x : last) {
          if(x != -1) {
            c++;
          }
        }
      }
      if(c >= 2) {
        chooseBiggest(last, nbiggest, c);
        if(biggest != nbiggest) {
          biggest = nbiggest;
          int from = start[a[i-1]-'a'];
          base = cnt[from][biggest[0]] - cnt[from][biggest[1]];
          res += pd->getRes();
          delete pd;
          pd = new PrevDiffs(0);
          for(int k=from+1;k<=i;k++) {
            pd->update(cnt[k][biggest[0]] - cnt[k][biggest[1]] - base);
          }
        }
        pd->update(cnt[i+1][biggest[0]] - cnt[i+1][biggest[1]] - base);
      }
    }
    res += pd->getRes();
    return res;
  }

  void chooseBiggest(vector<int>& last, vector<int>& biggest, int c) {
    int smallest = -1;
    if(c != 2) {
      smallest = 0;
      for(int k=1;k<3;k++) {
        if((last[k] != -1) && (last[k] < last[smallest])) {
          smallest = k;
        }
      }
    }
    int p = 0;
    for(int k=0;k<3;k++) {
      if((last[k] != -1) && (k != smallest)) {
        biggest[p] = k;
        p++;
      }
    }
  }

  ll countThreeLetters() {
    PrevDiffs pd(BASE << 32);
    int cnt[3] = {};
    for(int i=0;i<n;i++) {
      cnt[a[i]-'a']++;
      pd.update(((BASE + cnt[0] - cnt[1]) << 32) + cnt[0] - cnt[2]);
    }
    return pd.getRes();
  }
};

int main(int argc, char** argv) {
  int n = 0;
  char a[300123];
  scanf("%s", a);
  n = strlen(a);
  Solver solver(a, n);
  ll res = solver.solve();
  printf("%lld\n", res);
  return 0;
}