#include<bits/stdc++.h>
typedef long long lli;
using namespace std;
string s;
lli ans=1;
lli sum[26];
int main()
{
	cin>>s;
	for(int i=0;i<s.length();i++) sum[s[i]-'a']++;
	for(int i=1;i<26;i++) for(int j=0;j<i;j++) ans+=sum[i]*sum[j];
	printf("%lld",ans);
}
### Prompt

Please create a solution in Cpp 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>
typedef long long lli;
using namespace std;
string s;
lli ans=1;
lli sum[26];
int main()
{
	cin>>s;
	for(int i=0;i<s.length();i++) sum[s[i]-'a']++;
	for(int i=1;i<26;i++) for(int j=0;j<i;j++) ans+=sum[i]*sum[j];
	printf("%lld",ans);
}
```