#include <bits/stdc++.h>

using namespace std;

char s[200010];
int cnt[26];
typedef long long LL;

int main()
{
	scanf("%s",s);
	int len = strlen(s);
	LL ans = 1;
	LL sum = 0;
	for (int i=0;i<len;i++)
	{
		ans += sum - LL(cnt[s[i] - 'a']);
		cnt[s[i] - 'a']++;
		sum++;
	}
	printf("%lld\n",ans);
}
### Prompt

Generate 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;

char s[200010];
int cnt[26];
typedef long long LL;

int main()
{
	scanf("%s",s);
	int len = strlen(s);
	LL ans = 1;
	LL sum = 0;
	for (int i=0;i<len;i++)
	{
		ans += sum - LL(cnt[s[i] - 'a']);
		cnt[s[i] - 'a']++;
		sum++;
	}
	printf("%lld\n",ans);
}
```