Sorting bubble vs selection step by step

What is bubble sort?

A sorting algorithm that repeatedly steps through the list, compares adjacent elements, and swaps them if they are in the wrong order.

What is selection sort?

A sorting algorithm that divides the input into a sorted and an unsorted region, repeatedly selecting the smallest element from the unsorted region.

True or false: Bubble sort is always faster than selection sort.

False, because the performance depends on the data arrangement and size.

Main feature of bubble sort?

It continues to pass through the list until no swaps are needed, indicating the list is sorted.

Main feature of selection sort?

It finds the minimum element and swaps it with the first unsorted element until the whole list is sorted.

Difference between bubble sort and selection sort?

Bubble sort repeatedly swaps adjacent elements, while selection sort selects the smallest element from the unsorted portion.

What is the time complexity of bubble sort?

Average and worst-case time complexity is $\displaystyle O(n^2)$.

What is the time complexity of selection sort?

Average and worst-case time complexity is also $\displaystyle O(n^2)$.

Which algorithm is more memory efficient?

Both bubble sort and selection sort are in-place sorting algorithms, requiring $\displaystyle O(1)$ additional space.

Which sort is stable?

Bubble sort is stable while selection sort is not, meaning bubble sort maintains the relative order of equal elements.

Fill in the blank: Bubble sort is best for _____.

small datasets or nearly sorted lists.

Question: When would you use selection sort?

When memory write operations are costly and a simple algorithm is sufficient.

True or false: Selection sort always performs fewer swaps than bubble sort.

True, because selection sort makes at most $\displaystyle n-1$ swaps.

Comparison of efficiency: Bubble sort vs Selection sort?

Both have similar time complexity, but bubble sort can be more efficient with nearly sorted data.

What happens in the first pass of bubble sort?

The largest element bubbles to the top of the list after several comparisons.

What happens in the first pass of selection sort?

The smallest element is found and swapped with the first unsorted element.