#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
int c[226];
int main(){
    ios::sync_with_stdio(false);
    string s;cin >> s;
    for(auto cc:s) c[cc]++;
    ll n=s.size();ll ans=n*(n+1)/2+1;
    for(int i='a'; i<='z' ;i++) ans-=1LL*c[i]*(c[i]+1)/2;
    cout << ans << endl;
}
### Prompt

Please create a solution in CPP 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;
typedef long long ll;
int c[226];
int main(){
    ios::sync_with_stdio(false);
    string s;cin >> s;
    for(auto cc:s) c[cc]++;
    ll n=s.size();ll ans=n*(n+1)/2+1;
    for(int i='a'; i<='z' ;i++) ans-=1LL*c[i]*(c[i]+1)/2;
    cout << ans << endl;
}
```