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

int main() 
{
    long long ar[26]={0},i,j,n;
    string s;
    cin>>s;
    n=s.length();
    long long ans=1+n*(n-1)/2;
    for(i=0;i<n;++i)
    ++ar[s[i]-97];
    for(i=0;i<26;++i)
    ans=ans-ar[i]*(ar[i]-1)/2;
    cout<<ans<<endl;
	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;

int main() 
{
    long long ar[26]={0},i,j,n;
    string s;
    cin>>s;
    n=s.length();
    long long ans=1+n*(n-1)/2;
    for(i=0;i<n;++i)
    ++ar[s[i]-97];
    for(i=0;i<26;++i)
    ans=ans-ar[i]*(ar[i]-1)/2;
    cout<<ans<<endl;
	return 0;
}

```