#include <iostream>
#include <string>
using namespace std;

long long num[30];

int main()
{
	long long i,j,ans=0;
	string s;
	cin >> s;
	for(i=0;i<s.size();i++)
		num[s[i]-'a']++;
	for(i=0;i<s.size();i++)
		for(num[s[i]-'a']--,j=0;j<26;j++)
			if(j!=s[i]-'a') ans+=num[j];
	printf("%lld\n",ans+1);
} 
### Prompt

Generate 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 <iostream>
#include <string>
using namespace std;

long long num[30];

int main()
{
	long long i,j,ans=0;
	string s;
	cin >> s;
	for(i=0;i<s.size();i++)
		num[s[i]-'a']++;
	for(i=0;i<s.size();i++)
		for(num[s[i]-'a']--,j=0;j<26;j++)
			if(j!=s[i]-'a') ans+=num[j];
	printf("%lld\n",ans+1);
} 
```