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

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

    ll n = S.length();
    // i 文字目を MMA の二文字目としたときの MMA の総数
    vector<vector<ll>> sum(n, vector<ll>(26));
    for (ll i = n - 2; i >= 0; --i) {
        for (ll j = 0; j < 26; ++j) sum[i][j] = sum[i + 1][j];

        ll index = S[i] - 'A';
        sum[i][index] += n - i - 1;
    }
    // i 文字目までのアルファベットの個数
    vector<vector<ll>> num(n, vector<ll>(26));
    num[0][S[0] - 'A'] = 1;
    for (ll i = 1; i < n; ++i) {
        for (ll j = 0; j < 26; ++j) num[i][j] = num[i - 1][j];

        ll index = S[i] - 'A';
        num[i][index]++;
    }

    ll ans = 0;
    for (ll i = 0; i < n; ++i) {
        ll index = S[i] - 'A';

        if (num[i][index] == 1) continue;

        ll score = n - i - 1;
        ll tmp = sum[i][index] - (num[n - 1][index] - num[i][index]);
        ans += tmp;
    }

    cout << ans << endl;
}