#include<bits/stdc++.h>
#define maxn 2000100
#define LL long long 
using namespace std;
char str[maxn];
LL num[1000];
int main(){
	cin>>str;
	int n=strlen(str);
	LL ans=1;
	for(int i=0;i<n;i++){
		ans+=i-num[str[i]];
		num[str[i]]++;
	}
	cout<<ans;
	return 0;
}
### Prompt

Your challenge is to write 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 maxn 2000100
#define LL long long 
using namespace std;
char str[maxn];
LL num[1000];
int main(){
	cin>>str;
	int n=strlen(str);
	LL ans=1;
	for(int i=0;i<n;i++){
		ans+=i-num[str[i]];
		num[str[i]]++;
	}
	cout<<ans;
	return 0;
}
```