#include <bits/stdc++.h>

using namespace std;

long cnt[26];

int main(void){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	
	string str;
	cin>>str;
	
	long long ans = 1;
	for(long i = 0; i < str.size(); i++){
		ans = ans + i - cnt[str[i]-'a'];
		cnt[str[i]-'a']++;
	}
	
	cout<<ans;	
	return 0;
}
### 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 cnt[26];

int main(void){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	
	string str;
	cin>>str;
	
	long long ans = 1;
	for(long i = 0; i < str.size(); i++){
		ans = ans + i - cnt[str[i]-'a'];
		cnt[str[i]-'a']++;
	}
	
	cout<<ans;	
	return 0;
}
```