#include<iostream>
#include<algorithm>
using lint=int64_t;
using namespace std;

int main()
{
	string A;
	cin >> A;

	lint al[26]={};
	lint ans=1;

	for(int i=0;i<A.size();i++)
	{
		ans+=i-al[A[i]-'a'];
		al[A[i]-'a']++;
	}

	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<iostream>
#include<algorithm>
using lint=int64_t;
using namespace std;

int main()
{
	string A;
	cin >> A;

	lint al[26]={};
	lint ans=1;

	for(int i=0;i<A.size();i++)
	{
		ans+=i-al[A[i]-'a'];
		al[A[i]-'a']++;
	}

	cout << ans << endl;
	return 0;
}


```