#include <bits/stdc++.h>

using namespace std;

long long x[26];

int main() {
	string s;
	cin >> s;
	long long n = s.size(), ans = n * (n - 1) / 2 + 1;
	for (char c : s)
		x[c - 'a']++;
	for (int i = 0; i < 26; i++)
		ans -= x[i] * (x[i]- 1) / 2;
	cout << ans << '\n';
}
### Prompt

Your challenge is to write 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 <bits/stdc++.h>

using namespace std;

long long x[26];

int main() {
	string s;
	cin >> s;
	long long n = s.size(), ans = n * (n - 1) / 2 + 1;
	for (char c : s)
		x[c - 'a']++;
	for (int i = 0; i < 26; i++)
		ans -= x[i] * (x[i]- 1) / 2;
	cout << ans << '\n';
}
```