1
00:00:07,940 --> 00:00:14,220
Welcome back. What if we don't want to sort from the smallest item to the largest,

2
00:00:14,220 --> 00:00:18,375
but instead we want the reverse order? Well, that's easy.

3
00:00:18,375 --> 00:00:20,820
You've already seen how you can reverse a list,

4
00:00:20,820 --> 00:00:26,170
was actually a reverse function or you could do a list accumulation.

5
00:00:26,170 --> 00:00:30,140
But, it's actually even easier than that because we can

6
00:00:30,140 --> 00:00:34,805
specify an optional parameter for the sorted function called reverse.

7
00:00:34,805 --> 00:00:37,880
That's an optional parameter its default value,

8
00:00:37,880 --> 00:00:41,800
if you don't provide a value for it, it is false.

9
00:00:41,800 --> 00:00:44,680
But if you pass the value true in,

10
00:00:44,680 --> 00:00:47,435
you get the list back in the opposite order,

11
00:00:47,435 --> 00:00:51,780
you can see that on line number two.

12
00:00:52,240 --> 00:00:54,980
In addition to saying,

13
00:00:54,980 --> 00:00:57,270
what list we want to sort,

14
00:00:57,270 --> 00:01:03,075
we're also saying that the reverse parameter should get the value true.

15
00:01:03,075 --> 00:01:08,685
When we do that, we'll get the things in reverse order,

16
00:01:08,685 --> 00:01:11,945
Cherry, Blueberry, then Apple.

17
00:01:11,945 --> 00:01:14,975
I hope I'm not making it too hungry with these examples.

18
00:01:14,975 --> 00:01:20,630
So, this reverse equals true is just passing a parameter,

19
00:01:20,630 --> 00:01:24,200
the usual thing that we've seen before for functions.

20
00:01:24,200 --> 00:01:27,035
The actual value that we're passing in here,

21
00:01:27,035 --> 00:01:30,230
the word true is just a Boolean value,

22
00:01:30,230 --> 00:01:32,945
if you'll recall from when we were doing Boolean values.

23
00:01:32,945 --> 00:01:34,435
I could change this.

24
00:01:34,435 --> 00:01:36,915
Instead of passing the Boolean value true,

25
00:01:36,915 --> 00:01:39,285
I could pass the Boolean value false,

26
00:01:39,285 --> 00:01:45,719
and I would say, "Don't give this back in reverse order, not reversed."

27
00:01:45,719 --> 00:01:48,765
So, we would get Apple, Blueberry, and Cherry.

28
00:01:48,765 --> 00:01:54,589
Now, false is the default value for the reverse parameter.

29
00:01:54,589 --> 00:01:58,400
So, if I leave it out entirely,

30
00:01:58,400 --> 00:02:03,395
I get the same thing that I would get is if I say, "Reverse equals false."

31
00:02:03,395 --> 00:02:05,250
So, if I don't want it reversed,

32
00:02:05,250 --> 00:02:06,350
I don't have to say it.

33
00:02:06,350 --> 00:02:08,035
If I do want it reversed,

34
00:02:08,035 --> 00:02:11,380
I have to say "Reverse equals true."

35
00:02:11,440 --> 00:02:14,945
I get it in the reverse order.

36
00:02:14,945 --> 00:02:18,785
So, that's sorting a sequence in the opposite or the reverse order.

37
00:02:18,785 --> 00:02:22,385
I'll see you next time when we specify a custom order for sorting,

38
00:02:22,385 --> 00:02:26,760
based on some property of the items that are getting sorted.