Prerequisites: Binary Indexed Tree/ Policy Based Data Structure/ Merge sort
Explanation: This is a code for insertion sort. You have to count the number of swaps required to sort the array in non-decreasing order. This can be easily done using Binary Indexed Tree/ Policy Based Data Structure/Merge sort.
Binary Indexed Tree/Policy Based Data Structure: Count number of pairs such that where,
Merge Sort: Count number of swaps required during sorting the two halves and merging them.
Setter’s solution (using BIT): https://ideone.com/KG82oX
Alter’s solution (using PBDS): https://ideone.com/Wav3uC