#include<bits/stdc++.h>
#define neko 200010
#define f(i,a,b) for(register int i=(a);i<=(b);i=-(~i))
int cnt[30],len;
typedef long long ll;
ll ans=1;
char s[neko];
int main()
{
	scanf("%s",s),len=strlen(s)-1;
	f(i,0,len)ans+=i-cnt[s[i]-'a'],++cnt[s[i]-'a'];
	return printf("%lld\n",ans),0;
}
### 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>
#define neko 200010
#define f(i,a,b) for(register int i=(a);i<=(b);i=-(~i))
int cnt[30],len;
typedef long long ll;
ll ans=1;
char s[neko];
int main()
{
	scanf("%s",s),len=strlen(s)-1;
	f(i,0,len)ans+=i-cnt[s[i]-'a'],++cnt[s[i]-'a'];
	return printf("%lld\n",ans),0;
}
```