#include <iostream>
using namespace std;

string s;
int n;
int cnt[26];

int main() {
	cin >> s;
	for(char c: s) ++cnt[c-'a'];
	n = s.length();
	long long ans = 1LL*n*(n+1)/2LL+1LL;
	for(int i=0; i< 26; ++i) ans -= 1LL*cnt[i]*(cnt[i]+1)/2LL;
	cout << ans;
	return 0;
}
### Prompt

Construct a cpp code solution to the problem outlined:

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>
using namespace std;

string s;
int n;
int cnt[26];

int main() {
	cin >> s;
	for(char c: s) ++cnt[c-'a'];
	n = s.length();
	long long ans = 1LL*n*(n+1)/2LL+1LL;
	for(int i=0; i< 26; ++i) ans -= 1LL*cnt[i]*(cnt[i]+1)/2LL;
	cout << ans;
	return 0;
}
```