### Count Inversions In An Array | Set 1 (Using Merge Sort)

Dec 05, 2021 · Output: Number of inversions are 5. Complexity Analysis: Time Complexity: O(n log n), The algorithm used is divide and conquer, So in each level, one full array traversal is needed, and there are log n levels, so the time complexity is O(n log n). Space Complexity: O(n), Temporary array.. Note that the above code modifies (or sorts) the input array. If we want to …

### Merge Sort In C++ With Examples - Software Testing Help

Jan 04, 2022 · Merge sort uses the “divide and conquer” strategy which divides the array or list into numerous sub arrays and sorts them individually and then merges into a complete sorted array. Merge sort performs faster than other sorting methods and also works efficiently for smaller and larger arrays likewise.

### Merge Sort | Practice - GeeksforGeeks

Given an array arr[], its starting position l and its ending position r. Sort the array using merge sort algorithm. Example 1: Input: N = 5 arr[] = {4 1 3 9 7} Output: 1 3 4 7 9 Example 2: Input: N = 10 arr[] = {10 9 8 7 6 5 4 3 2 1} Output: 1