#include<cstdio>
#include<cstring>
#include<iostream>
typedef long long ll;
char a[2000010];
ll cnt[26];
int main(){
	scanf("%s",a);
	ll len=strlen(a),ans=len*(len-1)/2ll+1ll;
	for(int i=0;i<len;i++)cnt[a[i]-'a']++;
	for(int i=0;i<26;i++)ans-=cnt[i]*(cnt[i]-1ll)/2ll;
	std::cout<<ans<<std::endl;
	return 0;
}
### Prompt

Create a solution in CPP for 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<cstdio>
#include<cstring>
#include<iostream>
typedef long long ll;
char a[2000010];
ll cnt[26];
int main(){
	scanf("%s",a);
	ll len=strlen(a),ans=len*(len-1)/2ll+1ll;
	for(int i=0;i<len;i++)cnt[a[i]-'a']++;
	for(int i=0;i<26;i++)ans-=cnt[i]*(cnt[i]-1ll)/2ll;
	std::cout<<ans<<std::endl;
	return 0;
}
```