#include<iostream>
#include<cstring>
#include<set>
#define ll long long
using namespace std;
string s,temp,y;
ll len,ans,cnt[30],sum;
int main()
{
	cin>>s,len=s.length();
	ans=len*(len-1)/2,s=" "+s;
	for(int i=1;i<=len;i++) sum+=cnt[s[i]-'a'+1],cnt[s[i]-'a'+1]++;
	printf("%lld\n",ans-sum+1);
	return 0;
}
### Prompt

Construct a CPP code solution to the problem outlined:

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<set>
#define ll long long
using namespace std;
string s,temp,y;
ll len,ans,cnt[30],sum;
int main()
{
	cin>>s,len=s.length();
	ans=len*(len-1)/2,s=" "+s;
	for(int i=1;i<=len;i++) sum+=cnt[s[i]-'a'+1],cnt[s[i]-'a'+1]++;
	printf("%lld\n",ans-sum+1);
	return 0;
}
```