Minimum Number of Adjacent Swaps to Sort an Array

You are given an array of n integers. Your task is to compute the minimum number of adjacent swaps required to transform the array into a non-decreasing order.

This process is equivalent to counting the number of inversions in the array. In fact, the number of inversions can be represented by the formula:

$$ inversions = \sum_{1 \leq i A_j] $$

where \([A_i > A_j]\) equals 1 if \(A_i > A_j\) and 0 otherwise.

Note: You must read the input from stdin and output the answer to stdout.

inputFormat

The first line contains an integer n denoting the number of elements in the array. The second line contains n space-separated integers representing the array elements.

Example:
5
3 2 1 5 4

outputFormat

Output a single integer representing the minimum number of adjacent swaps required to sort the array in non-decreasing order.

Example:
4

## sample

5
3 2 1 5 4

4