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

long long c[255];

int main () {

    string s; cin >> s;
    long long n = s.size();

    long long ans = n*(n+1)/2;
    for (int i=0; i<n; i++) c[ s[i] ]++;
    for (int i='a'; i<='z'; i++) ans -= c[i]*(c[i]+1)/2;
    ans = ans+1;
    cout << ans << endl;
}

### Prompt

Your challenge is to write 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;

long long c[255];

int main () {

    string s; cin >> s;
    long long n = s.size();

    long long ans = n*(n+1)/2;
    for (int i=0; i<n; i++) c[ s[i] ]++;
    for (int i='a'; i<='z'; i++) ans -= c[i]*(c[i]+1)/2;
    ans = ans+1;
    cout << ans << endl;
}

```