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#include <cstdio>
#include <cstring>
#include <map>
#include <utility>
#include <cassert>
#define MAX_N 300011
using namespace std;

map<pair<int, int>, int> counts;
map<int, int> noA, noB, noC;
char s[MAX_N];

int main() {
    scanf("%s", s);
    int n = strlen(s);

    int db = 0;
    int dc = 0;

    int balNoA = 0; // B - C
    int balNoB = 0; // A - C
    int balNoC = 0; // A - B

    int justA = 0;
    int justB = 0;
    int justC = 0;

    long long res = 0;

    for (int i = 0; i < n; i++) {
        counts[make_pair(db, dc)]++;
        noA[balNoA]++;
        noB[balNoB]++;
        noC[balNoC]++;
        switch (s[i]) {
            case 'a':
                //3
                db--;
                dc--;
                //2
                noA.clear();
                balNoA = 0;
                balNoB++;
                balNoC++;
                //1
                justA++;
                justB = 0;
                justC = 0;

                break;
            case 'b':
                //3
                db++;
                //2
                noB.clear();
                balNoB = 0;
                balNoA++;
                balNoC--;
                //1
                justA = 0;
                justB++;
                justC = 0;
                break;
            case 'c':
                //3
                dc++;
                //2
                noC.clear();
                balNoC = 0;
                balNoA--;
                balNoB--;
                //1
                justA = 0;
                justB = 0;
                justC++;
                break;
            default:
                assert(false);
        }
        res += justA;
        res += justB;
        res += justC;
        res += noA[balNoA];
        res += noB[balNoB];
        res += noC[balNoC];
        res += counts[make_pair(db, dc)];
    }
    printf("%lld\n", res);
}