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

int main() {
  string A;
  cin >> A;
  vector<ll> cs(26);
  ll n = A.size();

  for (char c : A)
    cs[c - 'a']++;

  ll res = n * (n - 1) / 2 + 1;

  for (ll x : cs) {
    res -= x * (x - 1) / 2;
  }

  cout << res << endl;
}

### 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 <bits/stdc++.h>
using namespace std;
using ll = long long;

int main() {
  string A;
  cin >> A;
  vector<ll> cs(26);
  ll n = A.size();

  for (char c : A)
    cs[c - 'a']++;

  ll res = n * (n - 1) / 2 + 1;

  for (ll x : cs) {
    res -= x * (x - 1) / 2;
  }

  cout << res << endl;
}

```