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

int cnt[26];

int main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	string s;
	cin>>s;
	long long int ans=1;
	for(int i=0;i<s.size();i++){
		for(int j=0;j<26;j++)
			if((s[i]-'a')!=j)
				ans+=cnt[j];
		cnt[s[i]-'a']++;
	}
	cout<<ans<<endl;
}

### 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;

int cnt[26];

int main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	string s;
	cin>>s;
	long long int ans=1;
	for(int i=0;i<s.size();i++){
		for(int j=0;j<26;j++)
			if((s[i]-'a')!=j)
				ans+=cnt[j];
		cnt[s[i]-'a']++;
	}
	cout<<ans<<endl;
}

```