#include <bits/stdc++.h>
#define int long long
#define rep(i,n) for(int i=0;i<n;i++)
using namespace std;

string s;
int cnt[30];
signed main(){
	cin>>s;
	rep(i,s.size()){
		cnt[s[i]-'a']++;
	}
	int ans=s.size()*(s.size()-1)/2+1;
	rep(i,26){
		ans-=cnt[i]*(cnt[i]-1)/2;
	}
	cout<<ans<<endl;
}

### Prompt

Please provide a CPP coded solution 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>
#define int long long
#define rep(i,n) for(int i=0;i<n;i++)
using namespace std;

string s;
int cnt[30];
signed main(){
	cin>>s;
	rep(i,s.size()){
		cnt[s[i]-'a']++;
	}
	int ans=s.size()*(s.size()-1)/2+1;
	rep(i,26){
		ans-=cnt[i]*(cnt[i]-1)/2;
	}
	cout<<ans<<endl;
}

```