#include <iostream>
#include <string>
#include <algorithm>
#include <cmath>

using namespace std;
long long c[100];
int main()
{
	string str;
	long long s,i,n;
	cin >> str;
	s=str.size();
	n=s*(s-1)/2;
	for(i=0; i<s; i++)
		c[str[i]-97]++;
	for(i=0; i<26; i++)
	{
		n-=c[i]*(c[i]-1)/2;
	}
	cout << n+1;
}

### Prompt

Please provide a CPP coded solution to the problem described below:

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>
#include <algorithm>
#include <cmath>

using namespace std;
long long c[100];
int main()
{
	string str;
	long long s,i,n;
	cin >> str;
	s=str.size();
	n=s*(s-1)/2;
	for(i=0; i<s; i++)
		c[str[i]-97]++;
	for(i=0; i<26; i++)
	{
		n-=c[i]*(c[i]-1)/2;
	}
	cout << n+1;
}

```