#include <iostream>
#include <string>
using namespace std;

int ch[26];
int main() {
	string A; cin >> A;
	for(int i=0; i<A.size(); ++i) ++ch[A[i]-'a'];
	long ans=(long) 1+A.size()*(A.size()-1)/2;
	for(int i=0; i<26; ++i) ans -= (long) ch[i]*(ch[i]-1)/2;
	cout << ans << endl;
	return 0;
}

### Prompt

Please formulate 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;

int ch[26];
int main() {
	string A; cin >> A;
	for(int i=0; i<A.size(); ++i) ++ch[A[i]-'a'];
	long ans=(long) 1+A.size()*(A.size()-1)/2;
	for(int i=0; i<26; ++i) ans -= (long) ch[i]*(ch[i]-1)/2;
	cout << ans << endl;
	return 0;
}

```