#include <bits/stdc++.h>
using namespace std;
unsigned long long a[30]={},ans=0,l=0;
char c[200010]={};
int main(){
	scanf("%s",c+1),l=strlen(c+1);
	for(int i=1;i<=l;i++) a[c[i]-'a'+1]++;
	for(int i=1;i<26;i++) for(int j=i+1;j<=26;j++) ans+=a[i]*a[j];
	printf("%lld\n",ans+1);
}
### Prompt

Create a solution in cpp for 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;
unsigned long long a[30]={},ans=0,l=0;
char c[200010]={};
int main(){
	scanf("%s",c+1),l=strlen(c+1);
	for(int i=1;i<=l;i++) a[c[i]-'a'+1]++;
	for(int i=1;i<26;i++) for(int j=i+1;j<=26;j++) ans+=a[i]*a[j];
	printf("%lld\n",ans+1);
}
```