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## 3. Bubble Sort pseudocode

The pseudocode below is for the ascending order algorithm. Much like the searching algorithms, you may wish to revisit this page once you have a better grasp on the programming techniques and constructs laid out in our Programming section. For now, just follow the commentaries on each line.

Hover over each line to see the comment about it.

And for completeness sake, a small adjustment to the pseudocode will sort the list in descending order, the only line that changes is the one in red shown below, where the 'greater than' becomes 'less than'

```
data_set = [9,2,5,23,34,56]
last_exam_position = data_set.length - 2

swap = true

WHILE swap == true
swap = false
FOR i = 0 to last_exam_position
IF data_set[i] < data_set[i +1] THEN

temp = data_set[i+1]
data_set[i+1] = data_set[i]
data_set[i] = temp   // the swap is complete

swap = true
END IF
NEXT i
END WHILE

PRINT "List is now in descending order."
```

Challenge see if you can find out one extra fact on this topic that we haven't already told you

Click on this link: What is bubble sorting?