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

char A[200005];
int B[555];

ll Ans = 1;
int N;

int main() {
	scanf(" %s", A);
	N = int(strlen(A));
	for(int i = 0; i < N; i++) {
		B[A[i]]++;
		ll c = i - B[A[i]] + 1;
		Ans += c;
	}
	cout << Ans << endl;
	return 0;
}
### 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>
using namespace std;
typedef long long ll;

char A[200005];
int B[555];

ll Ans = 1;
int N;

int main() {
	scanf(" %s", A);
	N = int(strlen(A));
	for(int i = 0; i < N; i++) {
		B[A[i]]++;
		ll c = i - B[A[i]] + 1;
		Ans += c;
	}
	cout << Ans << endl;
	return 0;
}
```