Bubblesort is a sorting algorithm that can be described as: repeatedly make passes through the list, comparing adjacent elements, and swap them if they are out of order. Stop when a pass does not swap any elements.

$($a$)$ Give pseudocode for bubblesort.

$($b$)$ Analyze the best case and worst case runtimes of bubblesort using $\backslash$Theta $-$notation.