#include<bits/stdc++.h>
using namespace std;
long long len;
long long f[30];
char a[200010];
int main() {
	scanf("%s",a);
	long long len=strlen(a);
	for (int i=0;i<len;i++)
	 f[a[i]-'a']++;
	long long ans=len*(len-1)/2; 
	for (int i=0;i<26;i++)
	 ans-=f[i]*(f[i]-1)/2;
	printf("%lld\n",ans+1); 
}
### Prompt

Develop a solution in Cpp to the problem described below:

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;
long long len;
long long f[30];
char a[200010];
int main() {
	scanf("%s",a);
	long long len=strlen(a);
	for (int i=0;i<len;i++)
	 f[a[i]-'a']++;
	long long ans=len*(len-1)/2; 
	for (int i=0;i<26;i++)
	 ans-=f[i]*(f[i]-1)/2;
	printf("%lld\n",ans+1); 
}
```