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

string S; long long N, r, c[29];

int main() {
	cin >> S;
	N = S.size();
	for (int i = 0; i < N; i++) c[S[i] - 'a']++;
	
	r = N * (N - 1) / 2LL;
	for (int i = 0; i < 26; i++) r -= c[i] * (c[i] - 1LL) / 2LL;
	cout << r + 1LL << endl;
	return 0;
}
### 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 S; long long N, r, c[29];

int main() {
	cin >> S;
	N = S.size();
	for (int i = 0; i < N; i++) c[S[i] - 'a']++;
	
	r = N * (N - 1) / 2LL;
	for (int i = 0; i < 26; i++) r -= c[i] * (c[i] - 1LL) / 2LL;
	cout << r + 1LL << endl;
	return 0;
}
```