Describe the comb sort algorithm.

The comb sort algorithm is a comparison-based sorting algorithm that was developed by Włodzimierz Dobosiewicz in 1980. It is an improvement over the bubble sort algorithm and is known for its simplicity and efficiency.

The comb sort algorithm works by comparing elements that are far apart and gradually reducing the gap between them. It starts with a large gap between elements and compares and swaps elements that are that far apart. The gap is then reduced by a shrink factor, typically 1.3, and the process is repeated until the gap becomes 1. At this point, the algorithm performs a final pass using the bubble sort algorithm to ensure that the remaining elements are in the correct order.

The key idea behind the comb sort algorithm is that bubble sort is inefficient when there are small values at the end of the list, as they take a long time to "bubble" to their correct position. By using a larger gap initially, the comb sort algorithm can quickly move these small values towards the beginning of the list, reducing the number of comparisons and swaps required.

The pseudocode for the comb sort algorithm is as follows:

1. Initialize the gap as the length of the list.
2. Repeat the following steps until the gap becomes 1:
a. Set the gap to the floor division of the current gap by the shrink factor.
b. Iterate through the list from the beginning to the end - gap:
i. If the element at the current position is greater than the element at the current position + gap, swap them.
3. Perform a final pass using the bubble sort algorithm to ensure that the remaining elements are in the correct order.

The time complexity of the comb sort algorithm is O(n^2) in the worst case, but it can be improved to O(n log n) by using a different shrink factor. However, the comb sort algorithm is generally slower than more advanced sorting algorithms such as quicksort or mergesort.