#include<iostream>
#include<cstring>
#include<cstdio>
using namespace std;
int num[27];char c[300100];
long long ans=0;
int main()
{
	scanf("%s",c+1);int n=strlen(c+1);
	for(int i=n;i>=1;i--)ans+=(n-i)-num[c[i]-'a']++;
	printf("%lld",ans+1);return 0;
 } 
### Prompt

Please formulate 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<cstring>
#include<cstdio>
using namespace std;
int num[27];char c[300100];
long long ans=0;
int main()
{
	scanf("%s",c+1);int n=strlen(c+1);
	for(int i=n;i>=1;i--)ans+=(n-i)-num[c[i]-'a']++;
	printf("%lld",ans+1);return 0;
 } 
```