#include <bits/stdc++.h>
#define ll long long

using namespace std;

int main() {
    string s;
    cin >> s;
    int n = s.length();
    ll ans = n * 1LL * (n - 1) / 2;
    unordered_map <char, int> m;
    for (char z : s) {
        ans -= m[z];
        m[z]++;
    }
    ans++;
    cout << ans << endl;
}

### 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>
#define ll long long

using namespace std;

int main() {
    string s;
    cin >> s;
    int n = s.length();
    ll ans = n * 1LL * (n - 1) / 2;
    unordered_map <char, int> m;
    for (char z : s) {
        ans -= m[z];
        m[z]++;
    }
    ans++;
    cout << ans << endl;
}

```