Bubble sort, sometimes referred to as sinking sort, is a simple sorting algorithm that repeatedly steps through the list,\
compares adjacent elements and swaps them if they are in the wrong order.
The pass through the list is repeated until the list is sorted.
Take an array of numbers "5 1 4 2 8", and sort the array from lowest number to greatest number using bubble sort.
In each step, elements written in bold are being compared. Three passes will be required;
( 5 1 4 2 8 ) → ( 1 5 4 2 8 ), Here, algorithm compares the first two elements, and swaps since 5 > 1.
( 1 5 4 2 8 ) → ( 1 4 5 2 8 ), Swap since 5 > 4
( 1 4 5 2 8 ) → ( 1 4 2 5 8 ), Swap since 5 > 2
( 1 4 2 5 8 ) → ( 1 4 2 5 8 ), Now, since these elements are already in order (8 > 5), algorithm does not swap them.
( 1 4 2 5 8 ) → ( 1 4 2 5 8 )
( 1 4 2 5 8 ) → ( 1 2 4 5 8 ), Swap since 4 > 2
( 1 2 4 5 8 ) → ( 1 2 4 5 8 )
( 1 2 4 5 8 ) → ( 1 2 4 5 8 )
Now, the array is already sorted, but the algorithm does not know if it is completed.
The algorithm needs one additional whole pass without any swap to know it is sorted.
( 1 2 4 5 8 ) → ( 1 2 4 5 8 )
( 1 2 4 5 8 ) → ( 1 2 4 5 8 )
( 1 2 4 5 8 ) → ( 1 2 4 5 8 )
( 1 2 4 5 8 ) → ( 1 2 4 5 8 )