#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
using ld = long double;
using mint = modint998244353;

ll sum[26][202020];

int main() {
  string S; cin >> S;
  for (int i = 0; i < S.size(); i++) {
    for (int j = 0; j < 26; j++) {
      sum[j][i + 1] = sum[j][i] + (j == S[i] - 'A');
    }
  }
  ll ans = 0;
  for (int i = 0; i < S.size(); i++) {
    for (int j = 0; j < 26; j++) {
      if (j != S[i] - 'A' && sum[j][i + 1] >= 2) ans += sum[j][i + 1] * (sum[j][i + 1] - 1) / 2;
    }
  }
  cout << ans << endl;
  return 0;
}