#include <bits/stdc++.h>

using namespace std;

int i, n, cnt[1000]; string a;
long long ans = 0;

int main()
{
    cin >> a;
    for(i=0; i<a.size(); ++i)
    {
        ans += i - cnt[a[i]];
        ++cnt[a[i]];
    }

    cout << ans + 1 << '\n';

    return 0;
}

### 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;

int i, n, cnt[1000]; string a;
long long ans = 0;

int main()
{
    cin >> a;
    for(i=0; i<a.size(); ++i)
    {
        ans += i - cnt[a[i]];
        ++cnt[a[i]];
    }

    cout << ans + 1 << '\n';

    return 0;
}

```