#include <bits/stdc++.h>
using namespace std;
#define int long long
signed main(){
  string S;
  cin>>S;
  int N = S.size();
  vector<vector<int>> R(26,vector<int>(N+1));
  for(int i=0;i<N;i++)for(int j=0;j<26;j++){
  	R[j][i+1] = R[j][i]+(S[i]-'A'==j);
  }
  int ans = 0;
  for(int i=1;i<N-1;i++){
  	int k = S[i]-'A';
  	ans += R[k][i]*(N-1-i-(R[k][N]-R[k][i+1]));
  }
  cout<<ans<<endl;
}