#include<iostream>
#include<cstring>
using namespace std;
typedef long long ll;
int main(){
	string s;
	cin>>s;
	ll total=0;
	int a[26];
	memset(a,-1,sizeof(a)); 
	a[s[0]-'a']=0;
	total=s.size(); 
	for(int i=1;i<s.size();i++){
		total+=(i-a[s[i]-'a'])*(s.size()-i);
		a[s[i]-'a']=i;
	}
	cout<<total;
  	return 0;
}