#include <iostream>
#include <cstdio>
using namespace std;

long long n, ans, c[150];
string a;
int main()
{
	int i;
	cin >> a;
	n = a.size();
	for (i = 0; i < n; i++) c[a[i]]++;
	ans = n * (n - 1) / 2 + 1;
	for (i = 'a'; i <= 'z'; i++) ans -= c[i] * (c[i] - 1) / 2;
    cout << ans << endl;
    return 0;
}
### Prompt

Please create a solution in Cpp 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 <iostream>
#include <cstdio>
using namespace std;

long long n, ans, c[150];
string a;
int main()
{
	int i;
	cin >> a;
	n = a.size();
	for (i = 0; i < n; i++) c[a[i]]++;
	ans = n * (n - 1) / 2 + 1;
	for (i = 'a'; i <= 'z'; i++) ans -= c[i] * (c[i] - 1) / 2;
    cout << ans << endl;
    return 0;
}
```