#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
int main() {
	string s; 
	cin >> s; 
	int n = s.size();
	long long ans = 0;
	long long cnt[33] = {};
	for(long long i=0;i<n;i++){
		ans+=(i-cnt[s[i]-'a']);
		cnt[s[i]-'a']++;
	}
	cout<<ans+1ll<<endl;
	return 0;
}

### Prompt

Your task is to create 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;
int main() {
	string s; 
	cin >> s; 
	int n = s.size();
	long long ans = 0;
	long long cnt[33] = {};
	for(long long i=0;i<n;i++){
		ans+=(i-cnt[s[i]-'a']);
		cnt[s[i]-'a']++;
	}
	cout<<ans+1ll<<endl;
	return 0;
}

```