#include <iostream>

using namespace std;
int const nmax = 200000;

int frec[30];
char line[5 + nmax];

int main()
{
  char c;
  long long sum = 1;
  int n = 1;
  cin>>(line + 1);
  while(line[n] != 0){
    frec[line[n] - 'a']++;
    sum += n - frec[line[n] - 'a'];
    n++;
  }
  cout<<sum;

  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 <iostream>

using namespace std;
int const nmax = 200000;

int frec[30];
char line[5 + nmax];

int main()
{
  char c;
  long long sum = 1;
  int n = 1;
  cin>>(line + 1);
  while(line[n] != 0){
    frec[line[n] - 'a']++;
    sum += n - frec[line[n] - 'a'];
    n++;
  }
  cout<<sum;

  return 0;
}

```