#include <bits/stdc++.h>
#define ll long long
using namespace std;
ll ans=1;
char s[200005];
int t[27];
int main (){
	scanf ("%s",s+1);
	int len=strlen(s+1),i;
	for (i=len;i>=1;i--)
	{ans+=(len-i-t[s[i]-'a']);
	t[s[i]-'a']++;
	}
	printf ("%lld\n",ans);
	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 <bits/stdc++.h>
#define ll long long
using namespace std;
ll ans=1;
char s[200005];
int t[27];
int main (){
	scanf ("%s",s+1);
	int len=strlen(s+1),i;
	for (i=len;i>=1;i--)
	{ans+=(len-i-t[s[i]-'a']);
	t[s[i]-'a']++;
	}
	printf ("%lld\n",ans);
	return 0;
}
	
```