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Count Triplets Challenge

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You are given an array and you need to find number of tripets of indices (i, j, k) such that the elements at those indices are in geometric progression for a given common ratio r and i < j < k.

For example, arr=\left[1,4,16,64\right]. If r=4, we have \left[1,4,16\right] and \left[4,16,64\right] at indices (0, 1, 2) and (1, 2, 3).

Function Description
Complete the countTriplets function in the editor below. It should return the number of triplets forming a geometric progression for a given r as an integer. countTriplets has the following parameter(s):
* arr: an array of integers
* r: an integer, the common ratio

Input Format
The first line contains two space-separated integers n and r, the size of arr and the common ratio.

The next line contains n space-seperated integers arr\left[i\right].

Constraints
* 1 \le n \le 10^5
* 1 \le r \le 10^9
* 1 \le arr\left[i\right] \le 10^9

Output Format
Return the count of triplets that form a geometric progression.


Sample Input 0

Sample Output 0

Explanation 0
There are 2 triplets in satisfying our criteria, whose indices are (0,1,3) and (0,2,3)

Sample Input 1

Sample Output 1

Explanation 1
The triplets satisfying are index (0,1,2), (0,1,3), (1,2,4), (1,3,4), (1,4,5) and (3,4,5).

Solution