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

int main() {
	string s;
	cin >> s;
	vector<ll> m(26);
	for (auto c : s) {
		m[c - 'a']++;
	}
	ll n = (s.size() - 1) * s.size() / 2 + 1;
	for (auto e : m) {
		n -= (e - 1) * e / 2;
	}
	cout << n << endl;
	return 0;
}

### Prompt

Construct a cpp code solution to the problem outlined:

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;
	vector<ll> m(26);
	for (auto c : s) {
		m[c - 'a']++;
	}
	ll n = (s.size() - 1) * s.size() / 2 + 1;
	for (auto e : m) {
		n -= (e - 1) * e / 2;
	}
	cout << n << endl;
	return 0;
}

```