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

const ll p = 998244353;

string s;
ll n, ct[26], ans;

int main() {
	cin >> s;
	n = s.length();
	ans = n*(n-1)/2;
	for (int i = 0; i < n; ++i)
		ct[s[i]-'a']++;
	for (int i = 0; i < 26; ++i)
		ans -= ct[i]*(ct[i]-1)/2;
	cout << ans+1 << endl;
}
### Prompt

Your challenge is to write 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;
typedef long long ll;

const ll p = 998244353;

string s;
ll n, ct[26], ans;

int main() {
	cin >> s;
	n = s.length();
	ans = n*(n-1)/2;
	for (int i = 0; i < n; ++i)
		ct[s[i]-'a']++;
	for (int i = 0; i < 26; ++i)
		ans -= ct[i]*(ct[i]-1)/2;
	cout << ans+1 << endl;
}
```