#include <iostream>
#include <string>
#include <set>
#include <map>
using ll = long long;
using llu = long long unsigned;

using namespace std;

int main() {
    string S;
    cin >> S;

    map<char, int> data;
    for (auto c : S) { data[c]++; }

    ll result = 0;
    for (int i=0; i<S.size(); i++) {
        int step = 0;
        int count = 1;
        char c1 = S[i];
        if (data[c1] < 2) { continue; }
        for (int j=i; j<S.size(); j++) {
            switch(step) {
                case 0:
                case 1:
                    if (S[j]==c1) { step++; }
                    break;
                case 2:
                    if (S[j]!=c1) { result+=count; }
                    else { count++; }
                    break;
            }
        }
    }
    cout << result << endl; return 0;
}