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#include <bits/stdc++.h>

using namespace std;

constexpr int MAXLEN = 300000;
constexpr int LETTERS = 3;

uint64_t total = 0;
int n;

vector<int> c[LETTERS];
vector<int> d[LETTERS];

void MakeC()
{
    vector<char> s(MAXLEN + 8);
    fgets(&s[0], MAXLEN + 1, stdin);
    s.resize(strlen(&s[0]));
    while (!s.empty() && !isalpha(s.back()))
        s.pop_back();
    n = s.size();
    for (int i = 0; i < 3; ++i) {
       c[i].resize(n + 1);
       c[i][0] = 0;
    }
    for (int j = 0; j < LETTERS; ++j)
        for (int i = 0; i < n; ++i)
            c[j][i + 1] = c[j][i] + ((s[i] - 'a') == j);
}

void MakeD()
{
    for (int i = 0; i < 3; ++i) {
       d[i].resize(n + 1);
       int j = (i + 1) % 3;
       for (int k = 0; k <= n; ++k)
           d[i][k] = c[j][k] - c[i][k];
    }
}

struct Bucket
{
    const vector<int>& next;
    int i;
    void operator++() { i = next[i]; }
    bool operator!=(const Bucket& o) const { return i != o.i; }
    int operator*() const { return i; }
    Bucket begin() { return *this; }
    Bucket end() { return Bucket{next, -1}; }
};

struct BucketMap
{
    vector<int> first, next;
    BucketMap() { first.resize(2 * n + 1, -1); next.resize(n + 1, -1); }
    bool HasKey(int v) const { return first[v] >= 0; }
    void Add(int i, int v) { next[i] = first[v]; first[v] = i; }
    void Del(int i, int v) { first[v] = next[i]; next[i] = -1; }

    struct Iterator
    {
       const BucketMap& m;
       int i;
       void Shift() { while(i < (int) m.first.size() && m.first[i] < 0) ++i; }
       void operator++() { ++i; Shift(); }
       bool operator!=(const Iterator& o) const { return i != o.i; }
       int operator*() const { return i; }
    };
    Iterator begin() { Iterator it{*this, 0}; it.Shift(); return it; }
    Iterator end() { return Iterator{*this, (int) first.size()}; }
    Bucket operator[](int v) const { return Bucket{next, first[v]}; }
};

void Count(const vector<int>& a, const vector<int>& b)
{
    BucketMap am, bm;
    for (int i = 0; i < (int) a.size(); ++i)
        am.Add(i, a[i] + n);
    vector<int> vals;
    vals.reserve(2 * n + 1);
    for (int v : am) {
        for (int i : am[v]) {
            int u = b[i] + n;
            if (!bm.HasKey(u))
                vals.push_back(u);
            bm.Add(i, u);
        }
        for (int u : vals) {
            int size = 0;
            for (;;) {
                int j = *bm[u];
                if (j < 0)
                    break;
                size++;
                bm.Del(j, u);
            }
            total += uint64_t(size) * (size - 1) / 2;
        }
        vals.clear();
    }
}

int main()
{
    MakeC();
    MakeD();
    for (int i = 0; i < 3; ++i) {
        int j = (i + 1) % 3;
        Count(c[i], c[j]);
        Count(c[i], d[j]);
    }
    Count(d[0], d[1]);
    printf("%lu\n", total);
    return 0;
}