#include<cstdio>
#include<algorithm>
#include<cstring>
#include<string> 
using namespace std;
char s[200010];
long long ans, cnt[2000];
int main() {
	scanf("%s", s);
	int n = strlen(s);
	for(int i = 0; i < n; i++) {
		ans += i - cnt[s[i]];
		cnt[s[i]]++;
	}
	printf("%lld", ans + 1);
} 
### 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<cstdio>
#include<algorithm>
#include<cstring>
#include<string> 
using namespace std;
char s[200010];
long long ans, cnt[2000];
int main() {
	scanf("%s", s);
	int n = strlen(s);
	for(int i = 0; i < n; i++) {
		ans += i - cnt[s[i]];
		cnt[s[i]]++;
	}
	printf("%lld", ans + 1);
} 
```