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

string s;
int cnt[26];

int main() {
    cin >> s;
    long long ans = 1;
    for (char c : s) {
        for (int i = 0; i < 26; i++) {
            if (c ^ (i + 'a')) ans += cnt[i];
        }
        cnt[c - 'a']++;
    }
    cout << ans << endl;
    return 0;
}
### Prompt

In Cpp, your task is to solve 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;

string s;
int cnt[26];

int main() {
    cin >> s;
    long long ans = 1;
    for (char c : s) {
        for (int i = 0; i < 26; i++) {
            if (c ^ (i + 'a')) ans += cnt[i];
        }
        cnt[c - 'a']++;
    }
    cout << ans << endl;
    return 0;
}
```