#include<iostream>
#include<string.h>
using namespace std;

int main(){
	char s[200020];
	cin>>s;

	long long int ar[26]={0},l = strlen(s);
	for(int i=0;i<l;i++) ar[s[i]-'a']++;
	long long int ans = l*(l-1)/2;
	for(int i=0;i<26;i++){
		ans -= ar[i]*(ar[i]-1)/2;
	}
	cout<<ans+1;
	return 0;
}
### Prompt

Generate 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<iostream>
#include<string.h>
using namespace std;

int main(){
	char s[200020];
	cin>>s;

	long long int ar[26]={0},l = strlen(s);
	for(int i=0;i<l;i++) ar[s[i]-'a']++;
	long long int ans = l*(l-1)/2;
	for(int i=0;i<26;i++){
		ans -= ar[i]*(ar[i]-1)/2;
	}
	cout<<ans+1;
	return 0;
}
```