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

int main() {
    string s;
    cin >> s;
    int n = s.size();
    vector<long long> a(30, 0);
    long long ans = (long long)n*(n+1)/2;
    for (auto c : s) ++a[c-'a'];
    for (auto c : a) ans -= c*(c+1)/2;
    cout << ++ans << endl;
    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() {
    string s;
    cin >> s;
    int n = s.size();
    vector<long long> a(30, 0);
    long long ans = (long long)n*(n+1)/2;
    for (auto c : s) ++a[c-'a'];
    for (auto c : a) ans -= c*(c+1)/2;
    cout << ++ans << endl;
    return 0;
}
```