#include <iostream>
#include <string>
using namespace std;
string a;
long long ans,n,c[26];
int main(){
    cin>>a;
    n=a.size();
    ans=n*(n-1)/2;
    for(int i=0;i<n;i++)c[a[i]-'a']++;
    for(int i=0;i<26;i++)ans-=(c[i]-1)*c[i]/2;
    cout<<ans+1<<endl;
}
### Prompt

Your task is to create a cpp solution to 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 <iostream>
#include <string>
using namespace std;
string a;
long long ans,n,c[26];
int main(){
    cin>>a;
    n=a.size();
    ans=n*(n-1)/2;
    for(int i=0;i<n;i++)c[a[i]-'a']++;
    for(int i=0;i<26;i++)ans-=(c[i]-1)*c[i]/2;
    cout<<ans+1<<endl;
}
```