#include<bits/stdc++.h>
using namespace std;

char s[200005];

int n,cnt[200005];

long long ans;

int main(){
	scanf("%s",s+1);
	n=strlen(s+1);
	for(int i=1;i<=n;i++) cnt[s[i]-'a']++;
	for(int i=0;i<26;i++) for(int j=i+1;j<26;j++) ans+=1ll*cnt[i]*cnt[j];
	printf("%lld",ans+1);
}
### 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>
using namespace std;

char s[200005];

int n,cnt[200005];

long long ans;

int main(){
	scanf("%s",s+1);
	n=strlen(s+1);
	for(int i=1;i<=n;i++) cnt[s[i]-'a']++;
	for(int i=0;i<26;i++) for(int j=i+1;j<26;j++) ans+=1ll*cnt[i]*cnt[j];
	printf("%lld",ans+1);
}
```