Why is insertion sort better

Insertion sort is a simple sorting algorithm that is relatively efficient for small lists and mostly sorted lists, and often is used as part of more sophisticated algorithms.

Could you provide links to the related articles you don't understand? I'm not sure what aspects they might be addressing. Other than that, there is a theoretical difference which might be that bubble sort is more suited for collections represented as arrays than it is for those represented as linked lists , while insertion sort is suited for linked lists.

The reasoning would be that bubble sort always swaps two items at a time which is trivial on both, array and linked list more efficient on arrays , while insertion sort inserts at a place in a given list which is trivial for linked lists but involves moving all subsequent elements in an array to the right.

That being said, take it with a grain of salt. First of all, sorting arrays is, in practice, almost always faster than sorting linked lists. Simply due to the fact that scanning the list once has an enormous difference already. This is why other answers correctly claim insertion sort to be superior in general, and why I really wonder about the articles you read, because I fail to think of a simple way of saying this is better in cases A, and that is better in cases B.

In the best case scenario, i. I am doing my revision for the exam. Insertion sort is also more stable than Quick sort and requires less memory. This question describes some further benefits of insertion sort. Is there ever a good reason to use Insertion Sort?

When benchmarking sorting algorithms, I found out that switching from quicksort to insertion sort - despite what everybody was saying - actually hurts performance recursive quicksort in C for arrays larger than 4 elements.

And those arrays can be sorted with a size-dependent optimal sorting algorithm. That being said, always keep in mind that O n The speed depends on the implementation, e. Nevertheless, the second will probably be faster. O -notation is typically used to characterize performance for large problems, while deliberately ignoring constant factors and additive offsets to performance.

This is important because constant factors and overhead can vary greatly between processors and between implementations: the performance you get for a single-threaded Basic program on a machine will be very different from the same algorithm implemented as a C program running on an Intel i7-class processor.

Note that implementation optimization is also a factor: attention to detail can often get you a major performance boost, even if all other factors are the same! However, the constant factor and overhead are still important. O N log N doesn't come into play. Insertion sort is simple and, for small lists, it is generally faster than a comparably implemented quicksort or mergesort. That is why a practical sort implementation will generally fall back on something like insertion sort for the "base case", instead of recursing all the way down to single elements.

Its a matter of the constants that are attached to the running time that we ignore in the big-oh notation because we are concerned with order of growth. As c is quite small, for small n, the running time of insertion sort is less then that of Quicksort Good real-world example when insertion sort can be used in conjunction with quicksort is the implementation of qsort function from glibc.

The first thing to point is qsort implements quicksort algorithm with a stack because it consumes less memory, stack implemented through macros directives. Summary of current implementation from the source code you'll find a lot of useful information through comments if you take a look at it :. This is a big win, since insertion sort is faster for small, mostly sorted array segments. How about binary insertion sort?

You can absolutely search the position to swap by using binary search. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Overview of quicksort. The way that quicksort uses divide-and-conquer is a little different from how merge sort does. In merge sort, the divide step does hardly anything, and all the real work happens in the combine step. Quick Sort is also a cache friendly sorting algorithm as it has good locality of reference when used for arrays.

Quick Sort is also tail recursive, therefore tail call optimizations is done. Begin typing your search term above and press enter to search. Press ESC to cancel. Skip to content Home Engineering Which is faster insertion sort or merge sort? Ben Davis November 4, Which is faster insertion sort or merge sort?

Which sorting technique is better between quick sort and merge sort and why? What is the difference between quick sort and merge sort? What is the runtime of merge sort and why? Is Merge Sort difficult? Why is insertion sort better? When insertion sort is a good choice for sorting an array? Which sorting algorithm is best if list is already sorted?

What will be the number of passes to sort the elements using insertion sort?