#include<cstdio>
char c[200005];
int n;
long long ans,t[26];
int main()
{
	scanf("%s",c);
	for(int i=0;c[i]!='\0';++i)++n,t[c[i]-'a']++;
	for(int i=0;i<26;++i)ans+=t[i]*(n-t[i]);
	printf("%lld\n",ans/2+1);
	return 0;
}
### Prompt

Please create a solution in cpp 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<cstdio>
char c[200005];
int n;
long long ans,t[26];
int main()
{
	scanf("%s",c);
	for(int i=0;c[i]!='\0';++i)++n,t[c[i]-'a']++;
	for(int i=0;i<26;++i)ans+=t[i]*(n-t[i]);
	printf("%lld\n",ans/2+1);
	return 0;
}
```