#include<bits/stdc++.h>
#include<atcoder/all>
using namespace std;
using namespace atcoder;
using ll = int_fast64_t;
using ull = uint_fast64_t;

using mint = modint998244353;

constexpr ll INF = 1ll << 60;

#define iscontain(container, value) (find(container.begin(), container.end(), value) != container.end())

template<typename T, typename D> void printelem(const T& container, const D& divide){
	for(const auto& i : container) cout << i << divide;
	cout << endl;
}
template<typename T> void printelem(const T& container) { printelem(container, ", "); }
template<typename T> T input(){ T ret; cin >> ret; return ret; }

int main(){
	//インプット
	string S;
	cin >> S;

	map<char, vector<ll>> ch;
	for(ll i = 0; i < S.size(); i++) ch[S[i]].push_back(i);

	ll ans = 0;
	for(auto&& [_, i] : ch) if(i.size() >= 2){
		for(ll j = 1; j < i.size(); j++){
			ans += j * (S.size() - i[j] - 1 - (i.size() - j - 1));
		}
	}

	//アウトプット
	cout << ans;
	
	return 0;
}