#include <iostream>
#include <cassert>
#include <string>
#include <vector>
using namespace std;
using ll = long long;

void assert_str(string& s) {
    assert(3 <= s.length() && s.length() <= 200000);
    for (auto c : s) {
        assert('A' <= c && c <= 'Z');
    }
}

int main() {
    string s;
    cin >> s;
    assert_str(s);

    int n = s.length();
    vector cnt_sum('Z' + 1, vector<int>(n + 1));
    for (int i = 0; i < n; ++i) {
        cnt_sum[s[i]][i + 1] += 1;
        for (char c = 'A'; c <= 'Z'; ++c) {
            cnt_sum[c][i + 1] += cnt_sum[c][i];
        }
    }
    ll ans = 0;
    for (int i = 0; i < n; ++i) {
        for (char c = 'A'; c <= 'Z'; ++c) {
            if (s[i] == c) {
                continue;
            }
            ll cnt = cnt_sum[c][i];
            ans += cnt * (cnt - 1) / 2;
        }
    }
    cout << ans << endl;
    return 0;
}