#include <bits/stdc++.h>
using namespace std;
#define int long long

 //bool dp[2][4000001];

signed main(){
   string a;
   cin >>a;
   int k[26]={};
   for(int i=0;i<a.size();i++){
       k[a[i]-'a']++;
   }
   int ans=2;
   for(int i=0;i<26;i++)ans+=k[i]*(a.size() -k[i]);
   cout << ans/2;

    return 0;
}
### Prompt

In CPP, your task is to solve 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 int long long

 //bool dp[2][4000001];

signed main(){
   string a;
   cin >>a;
   int k[26]={};
   for(int i=0;i<a.size();i++){
       k[a[i]-'a']++;
   }
   int ans=2;
   for(int i=0;i<26;i++)ans+=k[i]*(a.size() -k[i]);
   cout << ans/2;

    return 0;
}
```