#include<bits/stdc++.h>
#define int long long
using namespace std;
signed main(){
  string S;
  cin>>S;
  int ans=(int)(S.size())*((int)(S.size())-1)/2+1;
  vector<int> A(26);
  for(char c:S){
    ans-=A[c-'a'];
    A[c-'a']++;
  }
  cout<<ans<<endl;
}
### Prompt

Create a solution in cpp for the following problem:

You have a string A = A_1 A_2 ... A_n consisting of lowercase English letters.

You can choose any two indices i and j such that 1 \leq i \leq j \leq n and reverse substring A_i A_{i+1} ... A_j.

You can perform this operation at most once.

How many different strings can you obtain?

Constraints

* 1 \leq |A| \leq 200,000
* A consists of lowercase English letters.

Input

Input is given from Standard Input in the following format:


A


Output

Print the number of different strings you can obtain by reversing any substring in A at most once.

Examples

Input

aatt


Output

5


Input

xxxxxxxxxx


Output

1


Input

abracadabra


Output

44

### Response

```cpp
#include<bits/stdc++.h>
#define int long long
using namespace std;
signed main(){
  string S;
  cin>>S;
  int ans=(int)(S.size())*((int)(S.size())-1)/2+1;
  vector<int> A(26);
  for(char c:S){
    ans-=A[c-'a'];
    A[c-'a']++;
  }
  cout<<ans<<endl;
}
```