#include<cstdio>
#include<algorithm>
using namespace std;
char p[301000];
long long S = 1;
int C[26];
int main(){
    int i, j;
    scanf("%s",p);
    for(i=0;p[i];i++)C[p[i]-'a']++;
    for(i=0;i<26;i++)for(j=i+1;j<26;j++)S += 1ll*C[i]*C[j];
    printf("%lld\n",S);
}
### Prompt

Please formulate 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<cstdio>
#include<algorithm>
using namespace std;
char p[301000];
long long S = 1;
int C[26];
int main(){
    int i, j;
    scanf("%s",p);
    for(i=0;p[i];i++)C[p[i]-'a']++;
    for(i=0;i<26;i++)for(j=i+1;j<26;j++)S += 1ll*C[i]*C[j];
    printf("%lld\n",S);
}
```