1 00:00:00,960 --> 00:00:04,670 Let's not look at other tech and we will also get them off it. 2 00:00:04,770 --> 00:00:12,900 We would see its usage as boutique Q as well as a stock as the name implies it is an implementation 3 00:00:12,990 --> 00:00:15,970 of a direct interface and is resizable. 4 00:00:16,500 --> 00:00:20,820 So internally it uses an Id just like an idealist. 5 00:00:21,090 --> 00:00:26,330 It was added in July 6 which means that it is a fairly new data structure. 6 00:00:26,760 --> 00:00:31,420 And since it is a deck we know that it can it both before and before. 7 00:00:32,160 --> 00:00:33,430 And these are the different ways. 8 00:00:33,500 --> 00:00:40,710 Creating an idyllic it can be unbonded or you can specify a fixed capacity or you can also construct 9 00:00:40,710 --> 00:00:44,670 it with the elements from the specified collection. 10 00:00:45,260 --> 00:00:51,270 Not that unlike a linked list which is also a deck other deck prohibits null values. 11 00:00:51,290 --> 00:00:58,890 Ok so you cannot add an old values and similarly unlikely English it does not implement the list interface 12 00:00:58,910 --> 00:00:59,150 . 13 00:00:59,460 --> 00:01:03,120 So it is a pure Q implementation. 14 00:01:03,120 --> 00:01:05,230 Novin we need to use a better implementation. 15 00:01:05,250 --> 00:01:09,230 It is recommended to use an Arabic rather than a linked list. 16 00:01:09,410 --> 00:01:11,340 And here are some reasons for that. 17 00:01:11,340 --> 00:01:13,640 One of them is from Java dock itself. 18 00:01:13,900 --> 00:01:20,310 It says that it is likely that an array deck is faster than linguist's if the linked list is used as 19 00:01:20,310 --> 00:01:22,350 a queue. 20 00:01:22,410 --> 00:01:28,030 There is also an article whose link is provided in the resources section and it proves that Arek is 21 00:01:28,040 --> 00:01:32,520 at on three times faster than a linked list for large groups. 22 00:01:32,520 --> 00:01:39,810 The main reason for that is that link list we have to create an additional node object with every newly 23 00:01:39,810 --> 00:01:41,510 added element right. 24 00:01:41,550 --> 00:01:48,000 We saw that in the linked list lecture that would take more time and would also mean more memory footprint 25 00:01:48,000 --> 00:01:48,990 . 26 00:01:48,990 --> 00:01:52,950 Similarly when the element is remote the object needs to be garbage collected. 27 00:01:53,140 --> 00:01:59,160 And so if there are a lot of elementary movers then it will load on the DC process. 28 00:01:59,280 --> 00:02:04,830 Also if you do a bit of hard thinking you make definitely come across this dot right. 29 00:02:04,830 --> 00:02:11,520 Why cant we use an idealist as if fearful we simply need to use the odd method for adding an element 30 00:02:11,520 --> 00:02:16,850 of pain and the removal of zero for removing the element from the head. 31 00:02:17,430 --> 00:02:23,070 There are few good reasons why you should not use another list on other deck would still be our best 32 00:02:23,070 --> 00:02:25,930 bet for you. 33 00:02:26,140 --> 00:02:28,170 One reason is performance. 34 00:02:28,170 --> 00:02:35,160 We know that in working remote off zero on an oral test which if all the subsequent elements. 35 00:02:35,160 --> 00:02:41,900 So it has a linear time complexity and it only gets back with a large number of elements because we 36 00:02:41,910 --> 00:02:44,580 how more and more dimensions. 37 00:02:45,150 --> 00:02:50,600 In fact according to one benchmark linked list was 20 times faster than our list product foredeck do 38 00:02:50,600 --> 00:02:58,130 you like Access 2000 elements who are used so Elliman chefs is definitely a killer. 39 00:02:58,530 --> 00:03:02,420 Link to the benchmark is included in the resources section. 40 00:03:02,970 --> 00:03:10,020 So you might next ask what about the men chef in an article as it is also at based base just like an 41 00:03:10,080 --> 00:03:11,230 idealist. 42 00:03:11,610 --> 00:03:17,340 We dont have 11 shifts bit with a deck as its implementation is based on something called its circular 43 00:03:17,360 --> 00:03:21,050 area which does not in ball and dimensions. 44 00:03:21,140 --> 00:03:21,540 OK. 45 00:03:21,630 --> 00:03:25,120 So it has more to do with the algorithm to make logic. 46 00:03:25,470 --> 00:03:31,180 So it would be constant time for adding and removing at both ends. 47 00:03:31,200 --> 00:03:37,680 Now another reason why idealists should not be used as a cue is your intention from a design perspective 48 00:03:37,690 --> 00:03:37,840 . 49 00:03:37,980 --> 00:03:44,190 Indention been using a red deck is to use it as a fee for Ardsley for which involves on the head or 50 00:03:44,190 --> 00:03:50,500 tail manipulations method names like pop beak and push very clearly reflect that. 51 00:03:51,030 --> 00:03:59,460 But with other list we did not constrain ourselves to or meet her dentate right under the complexities 52 00:03:59,460 --> 00:04:00,320 of the methods. 53 00:04:00,510 --> 00:04:07,950 Most methods run in a monetised Constantine that is then mostly constant time summiteers that deal with 54 00:04:07,950 --> 00:04:14,230 the remolding are searching for specific objects one billion years as we know because Can that you not 55 00:04:14,250 --> 00:04:19,750 that here we are talking about the remote off object method and not the moment. 56 00:04:19,840 --> 00:04:23,110 But empty parenthesis which is constant. 57 00:04:23,700 --> 00:04:30,630 Finally keep in mind that there is no way for us to add something in the middle Ah-Q all the internal 58 00:04:30,630 --> 00:04:34,710 elements can be deleted using these at the moment it's that busy here. 59 00:04:35,220 --> 00:04:36,390 So that's about it. 60 00:04:36,390 --> 00:04:40,580 No let's go ahead and Bushrod them off autistic. 61 00:04:41,910 --> 00:04:45,580 OK for this demo we're going to add a new class called that's cute. 62 00:04:45,610 --> 00:04:47,770 All of it is added to this package. 63 00:04:47,790 --> 00:04:54,620 Class collections that you deem a class has a motet deck test which we are going to fill in now. 64 00:04:54,870 --> 00:05:00,450 So it does not mean we are going to create an instance of our deck and we will use it as both a queue 65 00:05:00,570 --> 00:05:01,700 as well as us duck. 66 00:05:01,900 --> 00:05:04,290 OK so let's just go ahead and do that. 67 00:05:05,010 --> 00:05:13,950 So the reference type would be deck under deck which stored on these strings. 68 00:05:14,970 --> 00:05:18,550 Case select mean book already on deck. 69 00:05:20,240 --> 00:05:23,260 Now let's just go ahead and add some elements. 70 00:05:23,310 --> 00:05:24,720 So first let's do. 71 00:05:25,060 --> 00:05:26,550 Let's use it as a Q. 72 00:05:26,690 --> 00:05:32,820 OK which is official. 73 00:05:34,320 --> 00:05:36,460 Let's try to have some books here. 74 00:05:36,530 --> 00:05:37,930 That's our first book. 75 00:05:37,960 --> 00:05:40,620 Wilden a very nice book. 76 00:05:41,160 --> 00:05:50,100 A nineteenth century classic and lets out Harry Potter. 77 00:05:52,800 --> 00:06:00,740 And finally let's ired head first Java which is a great beginner level book quarte Java and there's 78 00:06:00,750 --> 00:06:03,680 also the commander and this course. 79 00:06:03,690 --> 00:06:13,650 Now let's put this statement here and let's say branding. 80 00:06:13,680 --> 00:06:18,780 Q And let's pretend all that three books. 81 00:06:18,840 --> 00:06:25,080 OK so this all goes space nuts. 82 00:06:25,140 --> 00:06:31,240 So we need to remove from the head and for that we know we can use the remote method. 83 00:06:31,530 --> 00:06:32,810 Right. 84 00:06:33,660 --> 00:06:36,710 So that would remove the element on would also get on that end. 85 00:06:36,810 --> 00:06:40,970 So let's call this let's do it. 86 00:06:41,010 --> 00:06:43,890 The second element also has the third element. 87 00:06:44,340 --> 00:06:50,460 Now it can be removed or you can also use it to move fast. 88 00:06:50,460 --> 00:06:50,800 Right. 89 00:06:50,820 --> 00:06:52,730 Because I've just got a Spawn's to head. 90 00:06:53,280 --> 00:06:55,480 So you just go ahead and run this. 91 00:06:55,540 --> 00:06:58,730 This method is and will Crome the main method. 92 00:06:58,970 --> 00:07:00,790 So it is bending the elements. 93 00:07:00,900 --> 00:07:06,540 So the first element that got added was Brandon underspending round and then the second element then 94 00:07:06,540 --> 00:07:07,350 the third element. 95 00:07:07,400 --> 00:07:09,420 OK so that is powerful. 96 00:07:09,700 --> 00:07:14,040 Now let's go ahead and also do the same for a stack. 97 00:07:14,040 --> 00:07:15,230 So let's implement as a stack. 98 00:07:15,270 --> 00:07:19,400 So at this point the deck is empty because we removed all the elements that what I did. 99 00:07:19,650 --> 00:07:21,860 So we can just reuse the same deck. 100 00:07:22,110 --> 00:07:30,240 I let's use it as a stack so let's just say stack last and just out. 101 00:07:30,330 --> 00:07:33,500 Now let's go ahead and push the same elements. 102 00:07:33,540 --> 00:07:33,750 OK. 103 00:07:33,750 --> 00:07:36,720 So let's use a push method. 104 00:07:37,980 --> 00:07:40,920 Don't push it 105 00:07:40,950 --> 00:07:51,770 . 106 00:07:51,860 --> 00:07:52,230 OK. 107 00:07:52,230 --> 00:07:56,500 So the elements have been pushed now to remove the elements. 108 00:07:56,490 --> 00:07:58,660 We can just use the pop method. 109 00:07:58,950 --> 00:08:05,060 So let me just copy this. 110 00:08:05,760 --> 00:08:10,540 This time it would be stuck. 111 00:08:12,720 --> 00:08:15,660 So here we just say pop 112 00:08:20,930 --> 00:08:26,780 that Sir sort of says go ahead and run it. 113 00:08:27,420 --> 00:08:30,370 Now as you can see the elements are the stack. 114 00:08:30,370 --> 00:08:33,900 They're getting pretty good in the reverse order because it doesn't last. 115 00:08:33,940 --> 00:08:35,170 And fast. 116 00:08:35,580 --> 00:08:39,150 So the last N elementals head first Java and that is garding. 117 00:08:39,200 --> 00:08:40,980 Bob don't just. 118 00:08:41,280 --> 00:08:42,420 So that's it. 119 00:08:42,420 --> 00:08:48,900 So stack is something we have already seen ret in GBM also the IBM also implements its metor in most 120 00:08:48,900 --> 00:08:50,290 patients using iStock. 121 00:08:50,540 --> 00:08:52,920 OK on is also used in many places. 122 00:08:52,950 --> 00:08:58,930 It's also used in a framework called Executive framework which you will see in the collections Shapter 123 00:08:59,460 --> 00:09:05,790 which is used to manage the threats threat management third management there the executive framework 124 00:09:05,850 --> 00:09:07,370 makes use of a. 125 00:09:07,530 --> 00:09:08,020 OK. 126 00:09:08,070 --> 00:09:10,980 So you is also used. 127 00:09:10,980 --> 00:09:11,910 So that's about it. 128 00:09:11,940 --> 00:09:13,170 So these are the things. 129 00:09:13,310 --> 00:09:18,950 And we also know that a linked list also implements direct interface. 130 00:09:19,280 --> 00:09:21,530 In addition to a list. 131 00:09:21,540 --> 00:09:23,940 So if we can import this 132 00:09:26,970 --> 00:09:28,220 and see the same output. 133 00:09:28,320 --> 00:09:30,180 So long list also can be used. 134 00:09:30,390 --> 00:09:35,460 But as we discussed earlier if you want a deck implementation you should go get utterer dick. 135 00:09:35,550 --> 00:09:37,910 OK so that's the recommended approach. 136 00:09:38,020 --> 00:09:40,020 Is that a commander implementation. 137 00:09:40,050 --> 00:09:40,680 So that's about it. 138 00:09:40,680 --> 00:09:41,160 Thank you. 139 00:09:41,160 --> 00:09:45,210 And you can find this code in the resources section and that's it. 140 00:09:45,210 --> 00:09:46,520 I'm happy coding.