#include <bits/stdc++.h>
using namespace std;

string a;
long long l, c[30], ans;

int main(){
	cin.tie(0);
	ios::sync_with_stdio(false);
	cin >> a;
	l = a.size();
	for(int i=0; i<l; ++i)
		++c[a[i]-'a'];
	ans = l * (l - 1) / 2;
	for(int i=0; i<26; ++i)
		ans -= c[i] * (c[i] - 1) / 2;
	cout << 1 + ans << "\n";
}
### Prompt

Please create a solution in cpp 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;

string a;
long long l, c[30], ans;

int main(){
	cin.tie(0);
	ios::sync_with_stdio(false);
	cin >> a;
	l = a.size();
	for(int i=0; i<l; ++i)
		++c[a[i]-'a'];
	ans = l * (l - 1) / 2;
	for(int i=0; i<26; ++i)
		ans -= c[i] * (c[i] - 1) / 2;
	cout << 1 + ans << "\n";
}
```