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Given an array **arr[]** of **N** integers, the task is to find the sum of the number of inversions in all subarrays of length **K**. To clarify, determine the number of inversions in each of the **n – k + 1** subarrays of length k and add them together.

**Example 1:**

**Input: **N = 4, K = 3
arr[]= {1, 6, 7, 2}**
Output:** 2
**Explanation**: There are two subarrays
of size 3, {1, 6, 7} and {6, 7, 2}.
Count of inversions in first subarray
is 0 and count of inversions in second
subarray is 2. So sum is 0 + 2 = 2.

**Example 2:**

**Input: **N = 8, K = 4**
**arr[]= {12, 3, 14, 8, 15, 1, 4, 22}
**Output:** 14

**Your Task:**

This is a function problem. You don't need to take any input, as it is already accomplished by the driver code. You just need to complete the function **inversion_count**() that takes array **a[], **integer **N, **and integer** K **as parameters and returns the desired result.

**Expected Time Complexity:** O(N^{2}).

**Expected Auxiliary Space:** O(N).

**Constraints:**

1 ≤ N ≤ 10^{3}

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Subarray Inversions

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