Answer:
6 2 and 0
Explanation:
This algorithm doesn't work if the list is not ordered ascending.
In this example it is not, and indeed the item "1" is never found.
first cycle: first=0, last=12 so midpoint=6
second cycle: first=0, last=5 so midpoint=2
last cycle: first=0, last=1 so midpoint=0
then last is assigned -1 so the while statement is no longer true.
