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#include <iostream>
#include <cstring>

using namespace std;

bool isBalanced(int count[], int length) {
    if (count[0] == length || count[1] == length || count[2] == length) {
        return true;
    }

    if (length % 2 == 0) {
        int half = length / 2;
        if ((count[0] == half && count[1] == half) ||
            (count[1] == half && count[2] == half) ||
            (count[0] == half && count[2] == half)) {
            return true;
        }
    }

    if (length % 3 == 0) {
        if (count[0] == count[1] && count[1] == count[2]) {
            return true;
        }
    }

    return false;
}

int main()
{
    ios::sync_with_stdio(false);
    //string s = "aabbabcccba";
    string s;
    cin >> s;

    int count[3] = { 0 };
    long long int balancedCount = s.size() + s.size() - 1;

    for (int currentLength = 3; currentLength <= s.size(); currentLength++) {
        //if (currentLength % 2 != 0 && currentLength % 3 != 0) {
        //    continue;
        //}

        memset(count, 0, sizeof(count));

        for (int i = 0; i < currentLength; i++) {
            count[s[i] - 'a']++;
        }

        if (isBalanced(count, currentLength)) {
            balancedCount++;
        }

        for (int i = currentLength; i < s.size(); i++) {
            count[s[i] - 'a']++;
            count[s[i - currentLength] - 'a']--;
            if (isBalanced(count, currentLength)) {
                balancedCount++;
            }
        }
    }


    cout << balancedCount << endl;
}