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

const int Nmax=200010;

int main() {
	string A;
	cin >> A;
	ll S[26]={};
	ll l=A.length();
	ll ans=(l*(l-1))/2+1;
	for(int i=0;i < l;i++)
		S[A[i]-'a']++;
	
	for(int i=0;i < 26;i++)
		ans -= S[i]*(S[i]-1)/2;
	
	cout << ans << endl;
	return 0;
}
### Prompt

In Cpp, your task is to solve 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;
typedef long long ll;

const int Nmax=200010;

int main() {
	string A;
	cin >> A;
	ll S[26]={};
	ll l=A.length();
	ll ans=(l*(l-1))/2+1;
	for(int i=0;i < l;i++)
		S[A[i]-'a']++;
	
	for(int i=0;i < 26;i++)
		ans -= S[i]*(S[i]-1)/2;
	
	cout << ans << endl;
	return 0;
}
```