// g++-13 1.cpp -std=c++17 -O2 -I .
#include <bits/stdc++.h>
using namespace std;

#include <atcoder/all>
using namespace atcoder;

using ll = long long;
using ld = long double;
 
using vi = vector<int>;
using vvi = vector<vi>;
using vll = vector<ll>;
using vvll = vector<vll>;
using vld = vector<ld>;
using vvld = vector<vld>;
using vst = vector<string>;
using vvst = vector<vst>;
 
#define fi first
#define se second
#define pb push_back
#define eb emplace_back
#define pq_big(T) priority_queue<T,vector<T>,less<T>>
#define pq_small(T) priority_queue<T,vector<T>,greater<T>>
#define all(a) a.begin(),a.end()
#define rep(i,start,end) for(ll i=start;i<(ll)(end);i++)
#define per(i,start,end) for(ll i=start;i>=(ll)(end);i--)
#define uniq(a) sort(all(a));a.erase(unique(all(a)),a.end())

int main(){
  ios::sync_with_stdio(false);
  cin.tie(nullptr);

  string s;cin>>s;
  
  int n=s.size();
  vi cnt(26,0);
  vi cnt2(26,0);

  ll ans=0;
  rep(i,0,n){
    cnt2[s[i]-'A']++;
  }

  rep(i,0,n){
    ans+=cnt[s[i]-'A']*(n-1-i-(cnt2[s[i]-'A']-cnt[s[i]-'A']-1));
    cnt[s[i]-'A']++;
  }

  cout<<ans<<endl;
}