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// 2021-0-zba-zbalansowane-slowa.cpp : This file contains the 'main' function. Program execution begins and ends there.
//
#define _CRT_SECURE_NO_WARNINGS 1
#include <cstdio>
#include <utility>
#include <algorithm>

constexpr int MAXN = 3e5 + 7;

char st[MAXN];

int arr[3];

std::pair<int, int> t1[MAXN];
int t2[MAXN];

long long db_hlp(char* s, int n, char l1, char l2)
{
    t2[0] = 0;
    for (size_t i = 0; i < n; i++)
    {
        t2[i + 1] = t2[i];
        if (s[i]==l1)
        {
            t2[i + 1]++;
        }
        if (s[i]==l2)
        {
            t2[i + 1]--;
        }
    }
    std::sort(t2, t2 + n + 1);
    long long answ = 0;
    for (long long i = 0; i <= n; )
    {
        long long j;
        for (j = i + 1; j <= n && t2[j] == t2[i]; j++);
        long long k = j - i;
        answ += k * (k - 1ll) / 2ll;
        i = j;
    }
    return answ;
}

long long db(int n, char l1, char l2, char l3)
{
    int lst = -1;
    st[n] = l1;
    long long answ = 0;
    for (int i = 0; i <= n; i++)
    {
        if (st[i]==l1)
        {
            answ += db_hlp(st + lst + 1, i - lst - 1, l2, l3);
            lst = i;
        }
    }
    return answ;
}

long long sngl(int n, char l)
{
    long long answ = 0;
    long long curlen=0;
    for (long long i = 0; i < n; i++)
    {
        if (st[i]==l)
        {
            curlen++;
        }
        else
        {
            answ += curlen * (curlen + 1ll) / 2ll;
            curlen = 0;
        }
    }
    return answ + curlen * (curlen + 1ll) / 2ll;
}

int main()
{
    int n;
    scanf("%s", st);
    for (n = 0; st[n] != 0; n++);
    for (size_t i = 0; i < n; i++)
    {
        t1[i + 1] = t1[i];
        switch (st[i])
        {
        case 'a':
            t1[i + 1].first--;
            t1[i + 1].second--;
            break;
        case 'b':
            t1[i + 1].first++;
            break;
        case 'c':
            t1[i + 1].second++;
            break;
        }
    }
    long long answ = 0;
    std::sort(t1, t1 + n + 1);
    for (long long i = 0; i <= n; )
    {
        long long j;
        for (j = i + 1; j <= n && t1[j] == t1[i]; j++);
        long long k = j - i;
        answ += k * (k - 1ll) / 2ll;
        i = j;
    }
    answ += db(n, 'a', 'b', 'c');
    answ += db(n, 'b', 'c', 'a');
    answ += db(n, 'c', 'a', 'b');
    answ += sngl(n, 'a');
    answ += sngl(n, 'b');
    answ += sngl(n, 'c');
    printf("%lld\n", answ);
}

// Run program: Ctrl + F5 or Debug > Start Without Debugging menu
// Debug program: F5 or Debug > Start Debugging menu

// Tips for Getting Started: 
//   1. Use the Solution Explorer window to add/manage files
//   2. Use the Team Explorer window to connect to source control
//   3. Use the Output window to see build output and other messages
//   4. Use the Error List window to view errors
//   5. Go to Project > Add New Item to create new code files, or Project > Add Existing Item to add existing code files to the project
//   6. In the future, to open this project again, go to File > Open > Project and select the .sln file