#include <bits/stdc++.h>
using namespace std;
const int N = 200000 + 10;
char s[N];
int a[N];
int main(){
    scanf("%s",s);
    int n = strlen(s);
    long long ans = 0;
    for(int i=n-1;i>=0;i--){
        ans += n-1-i-a[s[i]-'a'];
        a[s[i]-'a']++;
    }
    printf("%lld\n",ans+1);
}

### 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;
const int N = 200000 + 10;
char s[N];
int a[N];
int main(){
    scanf("%s",s);
    int n = strlen(s);
    long long ans = 0;
    for(int i=n-1;i>=0;i--){
        ans += n-1-i-a[s[i]-'a'];
        a[s[i]-'a']++;
    }
    printf("%lld\n",ans+1);
}

```