#include <bits/stdc++.h>

using namespace std;

int ap[26];
int32_t main() {


  string s;
  cin >> s;
  long long ans = 0;
  for(int i = 0; i < s.size(); ++i)
  {
      ++ap[s[i] - 'a'];
      ans += (i + 1) - ap[s[i] - 'a'];
  }
  cout << ans + 1;
}

### 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 ap[26];
int32_t main() {


  string s;
  cin >> s;
  long long ans = 0;
  for(int i = 0; i < s.size(); ++i)
  {
      ++ap[s[i] - 'a'];
      ans += (i + 1) - ap[s[i] - 'a'];
  }
  cout << ans + 1;
}

```