#include <iostream>
#include <string>
#include <vector>
#include <map>

using namespace std;

int main() {
	string s;
	cin >> s;
	int n = s.size();
	long long ans = 1;
	map < char, int > cnt;
	for (int i = n - 1; i >= 0; i--) {
		cnt[s[i]]++;
		ans += i + 1;
		ans -= cnt[s[i]];
	}
cout << ans << endl;
}
### Prompt

Develop a solution in cpp 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 <vector>
#include <map>

using namespace std;

int main() {
	string s;
	cin >> s;
	int n = s.size();
	long long ans = 1;
	map < char, int > cnt;
	for (int i = n - 1; i >= 0; i--) {
		cnt[s[i]]++;
		ans += i + 1;
		ans -= cnt[s[i]];
	}
cout << ans << endl;
}
```