#include <bits/stdc++.h>

using namespace std;

string a;
int ctr[26] = {};

int main()
{
  cin >> a;

  int64_t n = a.length();
  for (char c : a) ctr[c-'a']++;

  int64_t r = 1LL*n*(n-1)/2;
  for (int x : ctr) r -= 1LL*x*(x-1)/2;

  cout << r+1 << endl;

  return 0;
}

### Prompt

Construct a cpp code solution to the problem outlined:

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;

string a;
int ctr[26] = {};

int main()
{
  cin >> a;

  int64_t n = a.length();
  for (char c : a) ctr[c-'a']++;

  int64_t r = 1LL*n*(n-1)/2;
  for (int x : ctr) r -= 1LL*x*(x-1)/2;

  cout << r+1 << endl;

  return 0;
}

```