Count Inversions Problem Statement

Given an integer array ARR of size N, your task is to find the total number of inversions that exist in the array.

An inversion is defined for a pair of integers in the array when both of the following conditions are met:

ARR[i] ARR[j]

i

Question

Given an integer array ARR of size N, your task is to find the total number of inversions that exist in the array.

An inversion is defined for a pair of integers in the array when both of the following conditions are met:

Here, i and j are indices ranging from 0 to N-1.

N = 5
ARR = [2, 4, 1, 3, 5]

The inversions are: (2, 1), (4, 1), (4, 3), and hence the output is 3.

You are not required to print anything; it has been taken care of. Just implement the function to return the result.

Accepted Answer

Count the total number of inversions in an integer array.

Iterate through the array and for each pair of elements, check if the inversion condition is met.
Use a nested loop to compare each pair of elements efficiently.
Keep a count of the inversions found and return the total count at the end.

CodeNation Software Developer Intern interview questions & answers