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#include <iostream>
#include <cstdio>
#include <cstdint>
#include <cinttypes>
#include <cstring>
#include <vector>
#include <string>
#include <map>
#include <set>

using namespace std;

uint64_t solve_brut(const char *s)
{
    const uint64_t n = strlen(s);
    int exists[3];
    memset(exists, 0, sizeof(exists));

    static int cnt[300300][3];
    memset(cnt, 0, sizeof(cnt));
    for (int i = 0; i < n; i++) {
        if (i > 0) {
            for (int j = 0; j < 3; j++) {
                cnt[i][j] = cnt[i - 1][j];
            }
        }
        cnt[i][s[i] - 'a']++;
        exists[s[i] - 'a'] = 1;
    }

    uint64_t res = 0;
    for (int i = 0; i < n; i++) {
        for (int j = i; j < n; j++) {
            vector<int> diff(3); // number of a, b, c in the substring i..j

            for (int k = 0; k < 3; k++) {
                diff[k] = cnt[j][k];
                if (i > 0) diff[k] -= cnt[i - 1][k];
            }

            if ((diff[0] == diff[1] || diff[0] == 0 || diff[1] == 0) &&
                (diff[1] == diff[2] || diff[1] == 0 || diff[2] == 0) &&
                (diff[2] == diff[0] || diff[2] == 0 || diff[0] == 0)) {
                res++;
            }
        }
    }

    return res;
}

int main()
{
    static char s[300300];
   
    scanf("%s", s);

    uint64_t res = solve_brut(s);

    printf("%" PRIu64 "\n", res);

    return 0;
}