#include<bits/stdc++.h>
using namespace std;
 
char s[555333];
long long br[555];
 
int main() {
   scanf("%s", s);
   int n = strlen(s);
   for(int i=0; i<n; i++) br[s[i]]++;
   long long res = 0;
   for(int i='a'; i<='z'; i++) res += br[i] * (n-br[i]);
   printf("%lld\n", res/2 + 1);
   return 0;
}
### Prompt

Your task is to create 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;
 
char s[555333];
long long br[555];
 
int main() {
   scanf("%s", s);
   int n = strlen(s);
   for(int i=0; i<n; i++) br[s[i]]++;
   long long res = 0;
   for(int i='a'; i<='z'; i++) res += br[i] * (n-br[i]);
   printf("%lld\n", res/2 + 1);
   return 0;
}
```