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

ll N, cnt[26];
string s;

int main(){
    cin >> s; N = s.size();

    for(char c : s) cnt[c-'a']++;

    ll ans = N * (N-1) / 2 + 1;
    for(ll d : cnt) ans -= d * (d-1) / 2;

    cout << ans << endl;
    return 0;
}

### Prompt

Please formulate 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;
typedef long long ll;

ll N, cnt[26];
string s;

int main(){
    cin >> s; N = s.size();

    for(char c : s) cnt[c-'a']++;

    ll ans = N * (N-1) / 2 + 1;
    for(ll d : cnt) ans -= d * (d-1) / 2;

    cout << ans << endl;
    return 0;
}

```