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#include<bits/stdc++.h>

using namespace std;
typedef long long ll;
typedef pair<int, int> pii;

#define SIZE(a) ((int)a.size())

ll compute_single(string &s, char a) {
    ll res = 0;
    int len = 0;
    for(char c : s) {
        if(c == a) {
            len++;
        } else {
            len=0;
        }
        res+=len;
    }
    return res;
}

ll compute_pairs(string &s, char a, char b) {
    map<int, int> m;
    m[0] = 0;
    int diff = 0;
    ll res = 0;
    vector<int> dp(SIZE(s)+1);
    for(int i=0; i < SIZE(s); i++) {
        char c = s[i];
        if(c == a || c == b) {
            if(c == a) {
                diff++;
            } else {
                diff--;
            }
            if(m.count(diff)) {
                dp[i+1] = dp[m[diff]]+1;
            }
            m[diff] = i+1;
            res+=dp[i+1];
        } else {
            diff = 0;
            m.clear();
            m[0] = 0;
        }
    }
    return res;
}

ll compute_triples(string &s) {
    map<pii, int> m;
    int diff1=0, diff2=0;
    ll res = 0;
    vector<int> dp(SIZE(s)+1);
    m[{0, 0}] = 0;
    for(int i=0; i < SIZE(s); i++) {
        char c = s[i];
        if(c == 'a') {
            diff1++;
            diff2++;
        } else if(c == 'b') {
            diff1--;
        } else {
            diff2--;
        }
        if(m.count({diff1, diff2})) {
            dp[i+1] = dp[m[{diff1, diff2}]]+1;
        }
        m[{diff1, diff2}] = i+1;
        res+=dp[i+1];
    }
    return res;
}

int main() {
    ios_base::sync_with_stdio(0);
    string s;
    cin >> s;
    ll res = compute_single(s, 'a') + compute_single(s, 'b') + compute_single(s, 'c')
        + compute_pairs(s, 'a', 'b') + compute_pairs(s, 'b', 'c') + compute_pairs(s, 'c', 'a')
        + compute_triples(s);
    cout << res << "\n";
}