#include<bits/stdc++.h>
using namespace std;
#define ll long long
ll cnt[39];

int main(){
  string s;
  cin>>s;
  ll n=s.size();
  for(int i=0;i<n;i++){
    cnt[s[i]-'a']++;
  }
  ll sum=0;
  for(int i=0;i<27;i++){
    sum+=cnt[i]*(cnt[i]-1)/2;
  }
  cout<<n*(n-1)/2-sum+1<<endl;
  return(0);
}

### 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>
using namespace std;
#define ll long long
ll cnt[39];

int main(){
  string s;
  cin>>s;
  ll n=s.size();
  for(int i=0;i<n;i++){
    cnt[s[i]-'a']++;
  }
  ll sum=0;
  for(int i=0;i<27;i++){
    sum+=cnt[i]*(cnt[i]-1)/2;
  }
  cout<<n*(n-1)/2-sum+1<<endl;
  return(0);
}

```