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

int main()
{
  static char s[200010];
  scanf("%s",s);
  int n=strlen(s);
  int c[26]={0};
  long long ans=1;
  for(int i=0;i<n;i++){
    ans+=i-c[s[i]-'a'];
    c[s[i]-'a']++;
  }
  printf("%lld\n",ans);
  return 0;
}

### Prompt

Develop a solution in CPP to the problem described below:

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;

int main()
{
  static char s[200010];
  scanf("%s",s);
  int n=strlen(s);
  int c[26]={0};
  long long ans=1;
  for(int i=0;i<n;i++){
    ans+=i-c[s[i]-'a'];
    c[s[i]-'a']++;
  }
  printf("%lld\n",ans);
  return 0;
}

```