Sorting Algorithms Questions Long
The cocktail sort algorithm, also known as the bidirectional bubble sort or shaker sort, is a variation of the bubble sort algorithm. It is a simple comparison-based sorting algorithm that works by repeatedly swapping adjacent elements if they are in the wrong order. The cocktail sort algorithm differs from the bubble sort algorithm in that it sorts the list in both directions, from left to right and then from right to left, in each pass.
Here is a step-by-step description of the cocktail sort algorithm:
1. Start by initializing two pointers, one at the beginning of the list (left pointer) and the other at the end of the list (right pointer).
2. Set a flag variable, swapped, to track whether any swaps have been made during a pass. Initially, set swapped to false.
3. Begin the first pass from the left pointer to the right pointer. Compare adjacent elements and swap them if they are in the wrong order. If a swap is made, set swapped to true.
4. After reaching the right pointer, if no swaps have been made (swapped is still false), the list is already sorted, and the algorithm can terminate.
5. If swaps have been made, move the right pointer one position to the left.
6. Begin the second pass from the right pointer to the left pointer. Compare adjacent elements and swap them if they are in the wrong order. If a swap is made, set swapped to true.
7. After reaching the left pointer, if no swaps have been made (swapped is still false), the list is already sorted, and the algorithm can terminate.
8. If swaps have been made, move the left pointer one position to the right.
9. Repeat steps 3 to 8 until the list is fully sorted.
The cocktail sort algorithm is called bidirectional because it sorts the list in both directions, which helps to reduce the number of passes required to fully sort the list. By sorting from both ends, the largest elements gradually move towards the end of the list, while the smallest elements move towards the beginning.
The time complexity of the cocktail sort algorithm is O(n^2) in the worst case, where n is the number of elements in the list. However, in practice, it can be slightly more efficient than the bubble sort algorithm due to the bidirectional nature of the sorting process.