#include <stdio.h>
#include <atcoder/all>
#include <bits/stdc++.h>
using namespace std;
using namespace atcoder;
using mint = modint998244353;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf32 1000000001
#define Inf64 4000000000000000001



int main(){
	
	string s;
	cin>>s;
	
	map<char,long long> mp;
	long long ans = 0;
	rep(i,s.size()){
		long long t = mp[s[i]];
		mp[s[i]]++;
		t *= s.size()-1-i;
		ans += t;
	}
	for(auto x:mp){
		long long t = x.second;
		t *= x.second-1;
		t *= x.second-2;
		t /= 6;
		ans -= t;
	}
	cout<<ans<<endl;
	
	return 0;
}