#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    string s;
    cin >> s;
    int n = s.size();
    ll ans = 0;
    vector<array<ll, 26>> cnt(n + 1);
    array<ll, 26> tmp{};
    cnt[0] = tmp;
    for(int i = 0; i < n; i++){
        tmp[s[i] - 'A']++;
        cnt[i + 1] = tmp;
    }
    /*for(int j = 0; j < 26; j++){
        cerr << tmp[j] << " ";
    }
    cerr << '\n';*/
    for(int i = 0; i < n; i++){
        ll l = cnt[i][s[i] - 'A'];
        ll r = cnt[n][s[i] - 'A'] - cnt[i][s[i] - 'A'];
        ans += l * (n - i - r);
    }
    cout << ans << '\n';
}