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

int main(){
	string A;
	cin >> A;
	int N=A.size();
	
	long long ans=(long long)N*(N-1)/2+1;
	for(int i=0;i<26;i++){
		char t='a'+i;
		int c=0;
		for(auto a:A)if(a==t)c++;
		ans-=(long long)c*(c-1)/2;
	}
	cout << ans << endl;
	return 0;
}
### Prompt

Construct a Cpp code solution to the problem outlined:

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;

int main(){
	string A;
	cin >> A;
	int N=A.size();
	
	long long ans=(long long)N*(N-1)/2+1;
	for(int i=0;i<26;i++){
		char t='a'+i;
		int c=0;
		for(auto a:A)if(a==t)c++;
		ans-=(long long)c*(c-1)/2;
	}
	cout << ans << endl;
	return 0;
}
```