#include <bits/stdc++.h>
using namespace std;
typedef long long LL;

const int N=2e5+50;
char ch[N];
int n,cnt[26],s;
LL ans;
int main() {
	scanf("%s",ch+1); n=strlen(ch+1);
	for(int i=1;i<=n;i++)
		ans+=s-cnt[ch[i]-'a'], ++s, ++cnt[ch[i]-'a'];
	cout<<ans+1<<'\n';
}
### Prompt

Your task is to create 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>
using namespace std;
typedef long long LL;

const int N=2e5+50;
char ch[N];
int n,cnt[26],s;
LL ans;
int main() {
	scanf("%s",ch+1); n=strlen(ch+1);
	for(int i=1;i<=n;i++)
		ans+=s-cnt[ch[i]-'a'], ++s, ++cnt[ch[i]-'a'];
	cout<<ans+1<<'\n';
}
```