1 00:00:01,070 --> 00:00:02,040 Hey everybody. 2 00:00:02,040 --> 00:00:04,130 Welcome back to the voting party. 3 00:00:04,140 --> 00:00:06,620 Mark Price here at death's slopes of duck farm. 4 00:00:06,660 --> 00:00:14,280 And today we're going to talk about dictionaries and what I'd like you to do before we start is actually 5 00:00:14,280 --> 00:00:23,040 do me a favor and do a google search type in how do hash tables work in computer science how to hash 6 00:00:23,040 --> 00:00:28,440 tables work in computer science and go read some articles and start getting an idea of what a hash table 7 00:00:28,440 --> 00:00:33,450 is and then pauses video and go do that and come back here like in 15 minutes because I want you to 8 00:00:33,450 --> 00:00:35,820 have a base foundation. 9 00:00:35,820 --> 00:00:36,840 Did you do that. 10 00:00:36,840 --> 00:00:41,460 I'm sure you didn't because you listened to me until you start getting those job interviews and then 11 00:00:41,460 --> 00:00:42,960 they're like how does this work. 12 00:00:42,960 --> 00:00:48,030 You're like Mark you're right this whole time I should have been listening to what I just said and read 13 00:00:48,030 --> 00:00:49,640 about this and this and that and that. 14 00:00:49,650 --> 00:00:52,830 But instead I just was hoping that you had a video on it and whoa. 15 00:00:52,980 --> 00:00:54,690 But anyway I went to read it and I got the job. 16 00:00:54,780 --> 00:00:56,730 As always happens. 17 00:00:56,970 --> 00:00:57,640 Don't listen to me. 18 00:00:57,660 --> 00:00:59,130 Listen to me. 19 00:00:59,130 --> 00:00:59,530 Whatever. 20 00:00:59,550 --> 00:01:01,110 Do whatever you want your life. 21 00:01:01,110 --> 00:01:01,620 All right. 22 00:01:01,770 --> 00:01:07,810 So creating a new playground here and we're going to call this one dictionary. 23 00:01:08,370 --> 00:01:09,560 Dictionaries. 24 00:01:09,580 --> 00:01:16,590 So in Swift's hash table it's called the dictionary and in different languages the hash tables are hash 25 00:01:16,590 --> 00:01:19,850 maps or in this case dictionary here. 26 00:01:20,700 --> 00:01:24,350 And I'm going to go ahead and store this in my dictionaries folder. 27 00:01:25,100 --> 00:01:25,940 OK. 28 00:01:26,580 --> 00:01:31,690 There's a playground and I'm a pull up in this nice little info graphic that Apple has created. 29 00:01:32,010 --> 00:01:36,330 So there are three major collection types in swift. 30 00:01:36,510 --> 00:01:41,070 We have the array K which is N which is an ordered set. 31 00:01:41,370 --> 00:01:48,900 Excuse me an ordered list of items and you can have multiple values of the same type in an array. 32 00:01:48,900 --> 00:01:55,200 So for instance index 0 can have let's say the word six eggs but also index 5 could have the exact same 33 00:01:55,200 --> 00:01:55,710 word. 34 00:01:56,070 --> 00:01:57,260 Six makes doesn't matter. 35 00:01:57,390 --> 00:02:00,460 OK a linear list ordered items. 36 00:02:00,480 --> 00:02:01,090 OK. 37 00:02:01,410 --> 00:02:03,090 Now we've got something called a set. 38 00:02:03,150 --> 00:02:11,450 Now a set is has items that should only have one type of value meaning the values need to be unique 39 00:02:11,670 --> 00:02:12,680 but they're not ordered. 40 00:02:12,690 --> 00:02:14,730 OK but they are unique. 41 00:02:14,730 --> 00:02:16,950 And then we've got this cool thing here called the dictionary. 42 00:02:17,010 --> 00:02:19,800 Now you're going to use dictionaries and arrays more than your sets. 43 00:02:19,800 --> 00:02:24,730 When you're working with swift The dictionary has keys and values. 44 00:02:24,930 --> 00:02:30,420 And we're going to have an example similar to this today basically where the key is of a certain type. 45 00:02:30,570 --> 00:02:35,610 And then there is a value that's related to that key so that the values can all be the values can be 46 00:02:35,880 --> 00:02:41,080 the same as the other values of the other keys but the keys must always be unique. 47 00:02:41,250 --> 00:02:41,560 OK. 48 00:02:41,560 --> 00:02:43,130 And this is not ordered. 49 00:02:43,290 --> 00:02:43,940 OK. 50 00:02:44,160 --> 00:02:50,730 And there are actually very complex and efficient algebra algorithms working under the hood that help 51 00:02:50,730 --> 00:02:52,500 you retrieve and fetch items. 52 00:02:52,500 --> 00:02:55,900 Imagine if you had a dictionary that had a million keys in it. 53 00:02:55,920 --> 00:02:59,350 You know it's not going to go through the entire list of keys. 54 00:02:59,490 --> 00:03:04,530 It's going to start breaking things down and segregating out sections until it finds the key and the 55 00:03:04,530 --> 00:03:05,100 fastest route. 56 00:03:05,100 --> 00:03:07,620 Very complex things going underneath the hood. 57 00:03:07,620 --> 00:03:12,460 Again if you do that search I told you too on how to hash tables work. 58 00:03:12,510 --> 00:03:17,340 There's some amazing YouTube videos on how this actually works underneath the hood if you're into that 59 00:03:17,340 --> 00:03:18,110 kind of thing. 60 00:03:18,270 --> 00:03:22,770 And anyway so we're going to be working with the dictionary today and we're going to work with keys 61 00:03:22,830 --> 00:03:23,740 and values. 62 00:03:24,060 --> 00:03:27,900 So this is straight out of the Swift books with three e-book. 63 00:03:27,960 --> 00:03:30,320 Very important that you read that book. 64 00:03:30,510 --> 00:03:32,060 Of course I've said that before. 65 00:03:32,490 --> 00:03:34,410 And here we go. 66 00:03:34,500 --> 00:03:43,320 We're going to create our first dictionary names of this and I want I want you to do names of integers. 67 00:03:43,470 --> 00:03:52,950 Let's say we want a dictionary that lets us give a word a visual word that you can print out for a number 68 00:03:52,950 --> 00:03:58,620 type meaning like let's say I want the number three to say the word Three things like that. 69 00:03:58,620 --> 00:04:08,730 So what I can do is I can say names of integers equal or subscript here the square brace here and we're 70 00:04:08,730 --> 00:04:14,700 going to say three equals three. 71 00:04:14,700 --> 00:04:15,740 Now I know what you're thinking. 72 00:04:15,840 --> 00:04:17,810 Oh this is just like an array. 73 00:04:17,840 --> 00:04:19,650 This is like the third index right. 74 00:04:19,650 --> 00:04:21,220 No it is not. 75 00:04:21,240 --> 00:04:22,230 No it is not. 76 00:04:22,230 --> 00:04:26,880 This is actually the name of the key I just made the names of the keys of type int. 77 00:04:26,890 --> 00:04:31,980 OK this has nothing to do actually with an array it's not a subscript in that. 78 00:04:32,010 --> 00:04:34,170 You're grabbing an ordered amount of items. 79 00:04:34,170 --> 00:04:34,570 OK. 80 00:04:34,650 --> 00:04:39,270 This is just happened to be what I the type I chose for the key. 81 00:04:39,270 --> 00:04:41,880 This could also have been a string here which is interesting. 82 00:04:41,910 --> 00:04:46,200 So this is a simple example of your very first dictionary. 83 00:04:46,380 --> 00:04:50,670 And what we're doing here is we're just creating one on the fly. 84 00:04:50,670 --> 00:04:52,590 Initializing it using type inference. 85 00:04:52,590 --> 00:04:53,060 OK. 86 00:04:53,190 --> 00:04:57,750 We're creating a dictionary with a key of type and and a value of type string. 87 00:04:57,750 --> 00:05:01,990 I would not be able to do something like this and a three in here. 88 00:05:02,010 --> 00:05:02,530 OK. 89 00:05:02,660 --> 00:05:10,410 Because the value needs to be a string can assign value of type and destroying cast of keys and values. 90 00:05:10,470 --> 00:05:15,980 All of this may look familiar to you if you've worked with the race names of integers or see one more 91 00:05:16,370 --> 00:05:23,800 than let's say 44 equals forty four OK. 92 00:05:23,930 --> 00:05:31,160 The idea behind this dictionary is there's a unique key and then there's a value a word value for that 93 00:05:31,160 --> 00:05:34,250 we're just explaining in words so simple example. 94 00:05:34,250 --> 00:05:36,760 If you want to click quickly clear out a dictionary. 95 00:05:36,770 --> 00:05:38,490 Empty all the items out of it. 96 00:05:38,540 --> 00:05:41,900 It's as easy as doing this. 97 00:05:42,610 --> 00:05:48,650 OK square braces colon square braces it's going to clean out all of your keys and all of your values. 98 00:05:49,160 --> 00:05:52,320 Nice and you always do a more real world. 99 00:05:52,520 --> 00:05:53,980 Example let's say we have an app. 100 00:05:54,210 --> 00:05:54,900 OK. 101 00:05:55,580 --> 00:05:59,720 And let's talk about airports of the world we want to have an app that has all the airports of the world 102 00:05:59,770 --> 00:06:04,940 well every airport can only have one unique airport code. 103 00:06:04,940 --> 00:06:11,000 Imagine if airports had the same airport codes it would be crazy like imagine if Ireland had an LAX 104 00:06:11,240 --> 00:06:17,000 Los Angeles had an L.A. X you know and Dubai had an L.A. X wouldn't work that would mess things up so 105 00:06:17,050 --> 00:06:23,210 luckily we have unique airport codes that we can use throughout the world and each one has its own name 106 00:06:23,300 --> 00:06:24,120 its own unique name. 107 00:06:24,130 --> 00:06:25,340 And you know what. 108 00:06:25,430 --> 00:06:30,140 Maybe the airport codes are different and maybe two airports can have the exact same name but that wouldn't 109 00:06:30,140 --> 00:06:32,890 matter because it has its unique code and that's the most important thing. 110 00:06:32,900 --> 00:06:34,180 But we still need the name. 111 00:06:34,220 --> 00:06:38,240 So that's the advantage of using dictionaries is the Keys have to be unique. 112 00:06:38,420 --> 00:06:40,810 They have to be listed they're not secret or dictionary. 113 00:06:41,010 --> 00:06:42,670 Some of our airports. 114 00:06:42,920 --> 00:06:48,050 And this is going to be of type string so we're going to do it in explicitly declared dictionary. 115 00:06:48,050 --> 00:06:52,290 So the key is of type string and the value is of type string. 116 00:06:52,290 --> 00:06:54,780 Now let's go ahead and initialiser here right off the bat. 117 00:06:54,830 --> 00:07:00,500 So we're going to create some dictionary literals here that we're initialising right when we declare 118 00:07:00,530 --> 00:07:01,160 as well. 119 00:07:01,430 --> 00:07:03,080 So Toronto 120 00:07:06,140 --> 00:07:06,720 can't. 121 00:07:07,040 --> 00:07:14,420 So we've just created a dictionary that comes preloaded with one element in it or one key value combination. 122 00:07:14,420 --> 00:07:18,750 But we want to do more so we're going to put a comma here and then elex. 123 00:07:18,850 --> 00:07:19,500 OK. 124 00:07:19,840 --> 00:07:25,750 And what we're going to do is say loss or Los Angeles. 125 00:07:27,290 --> 00:07:28,340 Pretty cool actually. 126 00:07:28,370 --> 00:07:33,130 Los Angeles say international. 127 00:07:33,700 --> 00:07:34,240 OK. 128 00:07:34,400 --> 00:07:37,040 So and I actually commoner's not go there. 129 00:07:37,050 --> 00:07:38,070 There we go. 130 00:07:38,590 --> 00:07:39,040 OK. 131 00:07:39,230 --> 00:07:41,270 So what is happening here. 132 00:07:41,330 --> 00:07:43,730 So we put in the key name first and then a colon. 133 00:07:43,760 --> 00:07:44,070 OK. 134 00:07:44,130 --> 00:07:48,860 The colon separates the keeping the values of the key name goes first the call and then the value the 135 00:07:48,860 --> 00:07:52,670 comma separates the elements or the combinations. 136 00:07:52,670 --> 00:07:54,610 So this is one key value combination. 137 00:07:54,620 --> 00:07:56,810 This is a second and it's separated by a comma. 138 00:07:56,810 --> 00:08:04,780 So key name colon value comma key named colon value comma key name call and value comma. 139 00:08:05,360 --> 00:08:12,410 And we didn't have to explicitly declare it like so we could have used type inference and it should 140 00:08:12,410 --> 00:08:18,720 just work out of the box for us indicating that yes this is a string key and this is a string value. 141 00:08:18,770 --> 00:08:19,400 Pretty cool. 142 00:08:19,490 --> 00:08:24,080 So now we've got our dictionary full of airports and there's some of the other things we can do with 143 00:08:24,080 --> 00:08:25,010 this. 144 00:08:25,610 --> 00:08:37,790 We can print the Air Force dictionary has it lets you some string interpellation airports that count 145 00:08:39,470 --> 00:08:44,030 airport or Osei elements items. 146 00:08:44,790 --> 00:08:52,130 OK let's make this a little bigger here so you can see it's area. 147 00:08:52,460 --> 00:08:54,500 Put the quotation to soon. 148 00:08:54,500 --> 00:08:56,510 So the airport's dictionary has two items. 149 00:08:56,510 --> 00:08:57,080 Is that true. 150 00:08:57,260 --> 00:09:02,740 Yes it is one and two guys so you can get the count of a of a dictionary. 151 00:09:02,740 --> 00:09:07,460 And what else can we do if our ports is empty. 152 00:09:07,460 --> 00:09:09,220 You can see if it's empty or not. 153 00:09:09,500 --> 00:09:17,210 And we can print the airport's dictionary is empty. 154 00:09:17,720 --> 00:09:17,970 OK. 155 00:09:17,970 --> 00:09:19,280 So you can check if it's empty. 156 00:09:19,280 --> 00:09:24,300 The simple little command and you're probably wondering well how do I add new items to a dictionary. 157 00:09:24,330 --> 00:09:30,420 Well since we're not making an ordered array where an element goes onto the back of the list we're inserting 158 00:09:30,420 --> 00:09:32,210 at a certain place we don't care about that. 159 00:09:32,210 --> 00:09:33,860 All we care about is the key. 160 00:09:34,020 --> 00:09:37,470 So we can just say airports let's add a new one. 161 00:09:37,560 --> 00:09:41,310 LHR equals London. 162 00:09:42,210 --> 00:09:47,450 So what we're doing here is we're setting LHR. 163 00:09:47,460 --> 00:09:48,500 This is the key name. 164 00:09:48,620 --> 00:09:48,990 OK. 165 00:09:49,020 --> 00:09:55,590 We're set in that unique key key value to be of the value of the type and type but the value to be London. 166 00:09:55,590 --> 00:09:56,100 OK. 167 00:09:56,190 --> 00:09:59,860 So the unique key LHR is going to be equal to London. 168 00:10:00,080 --> 00:10:00,700 Okay. 169 00:10:00,750 --> 00:10:03,270 And we just added a new element at this point in time. 170 00:10:03,650 --> 00:10:06,590 Okay well what if we want to update this or override it. 171 00:10:06,780 --> 00:10:10,680 It's just as simple as doing the exact same thing. 172 00:10:11,190 --> 00:10:12,420 Okay. 173 00:10:16,630 --> 00:10:18,820 So what we did here was whatever was in that spot. 174 00:10:18,830 --> 00:10:20,030 We've now overwritten. 175 00:10:20,080 --> 00:10:21,190 It's gone. 176 00:10:21,190 --> 00:10:22,860 So that's how you replace elements. 177 00:10:22,870 --> 00:10:27,130 That's also up to elements did it matter if one of these key names existed before or not. 178 00:10:27,130 --> 00:10:31,640 No it does not matter because it will be created the moment you assign it there. 179 00:10:31,660 --> 00:10:36,790 OK so if you're thinking well there's nothing in there and I tried to assign some to it it's going to 180 00:10:36,790 --> 00:10:37,530 give me an error. 181 00:10:37,690 --> 00:10:38,450 That's not the case. 182 00:10:38,450 --> 00:10:42,230 Not unlike in an array where if you try and grab an item that doesn't exist. 183 00:10:42,360 --> 00:10:42,780 OK. 184 00:10:42,830 --> 00:10:45,260 You get the crash you know it's different here. 185 00:10:45,280 --> 00:10:46,300 OK. 186 00:10:47,470 --> 00:10:49,690 What else let's say airport. 187 00:10:51,130 --> 00:10:53,210 Loads up here. 188 00:10:54,500 --> 00:11:01,660 All right say airports credit Nouwen dev equals slopes International. 189 00:11:01,680 --> 00:11:08,260 Didn't you guys know that Dev slopes has its own airport now and we have Wi-Fi and roller coasters and 190 00:11:08,260 --> 00:11:09,080 birthday cakes. 191 00:11:09,080 --> 00:11:10,390 It's really cool. 192 00:11:11,110 --> 00:11:15,580 And then we realized it was a dream and it doesn't exist so how do we actually remove an item completely 193 00:11:15,580 --> 00:11:22,030 we want to go gone key and everything because there is no there's Loeb's airport with cakes and Wi-Fi 194 00:11:22,030 --> 00:11:24,060 and roller coasters would be cool. 195 00:11:24,070 --> 00:11:25,520 We probably had a draft in there too. 196 00:11:25,660 --> 00:11:32,720 But my dreams are now crushed so Everts dev Beagle's Neal. 197 00:11:33,190 --> 00:11:36,280 You can set it to nil which will completely destroy and remove the item. 198 00:11:36,280 --> 00:11:38,410 It is gone. 199 00:11:39,130 --> 00:11:43,060 So I hope you're starting to see oh I can work with keys and values they're unique. 200 00:11:43,060 --> 00:11:44,480 I can do different things with them. 201 00:11:44,530 --> 00:11:45,710 You're going to use these a lot. 202 00:11:45,770 --> 00:11:47,610 Hey we're just scratching the surface here. 203 00:11:47,620 --> 00:11:53,370 You can also iterate through through and a dictionary which is cool as well. 204 00:11:53,470 --> 00:11:56,360 You can get all the keys and values out of it which we'll do right now. 205 00:11:56,370 --> 00:12:08,070 So Kalsu they're here for each airport code an airport name in airports. 206 00:12:08,250 --> 00:12:08,460 OK. 207 00:12:08,470 --> 00:12:10,710 So what we're doing here is a for loop. 208 00:12:10,840 --> 00:12:11,640 OK. 209 00:12:11,680 --> 00:12:16,470 And the for loop in this case in a dictionary it's giving us what's called a tuple. 210 00:12:16,780 --> 00:12:24,760 OK a tuple is a data type or a data construct that has one or more elements in it. 211 00:12:24,910 --> 00:12:28,500 OK so it's returning as a tuple you don't have to remember that just know how to use this. 212 00:12:28,570 --> 00:12:29,210 OK. 213 00:12:29,310 --> 00:12:34,030 And what it's going to do is it's going to pass in the key name and the value. 214 00:12:34,030 --> 00:12:37,290 I could also have said key and Val. 215 00:12:37,560 --> 00:12:37,900 OK. 216 00:12:37,900 --> 00:12:38,980 Same exact thing. 217 00:12:38,980 --> 00:12:44,080 So it's going to give us the key name and the value and it's going to go through the entire dictionary 218 00:12:44,110 --> 00:12:45,060 on each one of those. 219 00:12:45,070 --> 00:12:49,900 And there is an algorithm that goes underneath the hood that's efficient and grabbing this information 220 00:12:50,400 --> 00:12:53,410 though not as efficient as other ways of accessing information. 221 00:12:53,410 --> 00:12:59,380 In most cases one in many cases you don't want to iterate through an entire list of dictionaries if 222 00:12:59,380 --> 00:13:05,110 you want to iterate through a list of something you know maybe an array is better data structure but 223 00:13:05,320 --> 00:13:10,590 you can definitely go through here and I have before so say airport code. 224 00:13:10,770 --> 00:13:11,260 All right. 225 00:13:11,410 --> 00:13:17,710 And then we'll put up the last call in here and then we're going to say airport name. 226 00:13:18,220 --> 00:13:18,720 OK. 227 00:13:19,000 --> 00:13:23,980 So we're just going to go through and print the code in the name or the key and the value. 228 00:13:23,980 --> 00:13:24,640 And here it is. 229 00:13:24,650 --> 00:13:29,740 There's the key there is the value there's the key there is the value key and value. 230 00:13:29,740 --> 00:13:30,900 OK. 231 00:13:31,810 --> 00:13:32,950 Looking good. 232 00:13:32,950 --> 00:13:34,280 Very good. 233 00:13:34,300 --> 00:13:34,690 All right. 234 00:13:34,690 --> 00:13:39,780 So there's our airport to airport name perfect gap. 235 00:13:40,390 --> 00:13:41,190 What else can we do. 236 00:13:41,200 --> 00:13:49,480 We can also just do the keys and values individually so each airport code or we can even just say for 237 00:13:49,480 --> 00:13:53,720 each key in air port Stuckey's. 238 00:13:54,070 --> 00:13:55,240 So you can print up the key is right 239 00:14:01,680 --> 00:14:02,580 when you pass in the key 240 00:14:06,310 --> 00:14:12,040 pretty cool and we can also do the same thing with the BIOS for each vowel. 241 00:14:12,150 --> 00:14:17,710 An airport style value is now valid just a variable that I've created a constant 242 00:14:20,490 --> 00:14:20,800 you 243 00:14:24,540 --> 00:14:29,000 organise mass and bell here OK so value value value. 244 00:14:29,050 --> 00:14:31,070 So you can work with kids and values. 245 00:14:31,090 --> 00:14:33,180 The kids are unique. 246 00:14:33,320 --> 00:14:38,190 You're mostly at most of the time you're going to work with strings here Njord in your data types you 247 00:14:38,190 --> 00:14:39,240 can play around with other things. 248 00:14:39,250 --> 00:14:43,810 But one of the big uses of dictionaries is when you're working with Jaison data that you're getting 249 00:14:43,810 --> 00:14:47,980 from the Internet it's going to come down in a bundle Jae's on file and you're going to grab things 250 00:14:47,980 --> 00:14:55,730 by keys and values because Jaison is very much similar to the notion of dictionary keys and values. 251 00:14:55,870 --> 00:14:59,810 And if you don't know what I'm talking about just take a look at it right here. 252 00:14:59,890 --> 00:15:06,670 You can go to a Star Wars API that's this free API that was created on the internet that has lots of 253 00:15:07,540 --> 00:15:09,250 information on it. 254 00:15:09,370 --> 00:15:11,480 And so right here it's pulling up some space on this one. 255 00:15:11,500 --> 00:15:12,770 Luke Skywalker. 256 00:15:13,000 --> 00:15:20,440 And so this is a dictionary where the Vout are the keys are of type string. 257 00:15:20,470 --> 00:15:23,280 So here's a key called name of type string. 258 00:15:23,440 --> 00:15:28,950 So name this string Luke Skywalker the value type of this one is a string. 259 00:15:28,960 --> 00:15:32,500 Let's find one that's not a string here. 260 00:15:32,560 --> 00:15:34,870 These are all strings on here. 261 00:15:34,870 --> 00:15:40,510 Let's look at some of their other API features to show you how it's going to kind of translate in your 262 00:15:40,510 --> 00:15:41,210 code. 263 00:15:45,130 --> 00:15:46,040 Israel strings as well. 264 00:15:46,040 --> 00:15:47,020 They could also been numbers. 265 00:15:47,020 --> 00:15:55,330 This this company or this person chose to put all the values in as strings instead of numbers so that's 266 00:15:55,330 --> 00:16:00,130 really important to to understand is when you download information from the internet or Jason you have 267 00:16:00,130 --> 00:16:02,350 to abide by whatever they have created for you. 268 00:16:02,350 --> 00:16:08,260 So whereas I may have put this as a number an integer they chose to use a string for both the key and 269 00:16:08,260 --> 00:16:08,650 the value. 270 00:16:08,650 --> 00:16:11,030 There's another API that I like to work with as well. 271 00:16:11,170 --> 00:16:14,390 OK mine are active pokey API. 272 00:16:14,980 --> 00:16:18,900 OK another one that somebody put up which is kind of cool. 273 00:16:19,540 --> 00:16:21,710 And here's one perfect example so. 274 00:16:22,020 --> 00:16:24,450 So this is a dictionary object right. 275 00:16:24,610 --> 00:16:27,100 And the keys are all strings. 276 00:16:27,220 --> 00:16:29,430 But in this case the key is. 277 00:16:29,490 --> 00:16:35,260 So the key ID has a value that's a number it's an integer and base experience is an integer. 278 00:16:35,260 --> 00:16:37,960 Height is an integer is default is a boolean. 279 00:16:37,960 --> 00:16:41,220 So you can have a boolean value type. 280 00:16:41,440 --> 00:16:44,710 So this is this is interesting to look at this one on this one. 281 00:16:44,710 --> 00:16:51,950 The key name is a string but the value is an array. 282 00:16:51,970 --> 00:16:52,930 That's really interesting. 283 00:16:52,930 --> 00:16:54,160 Can we do that with swift. 284 00:16:54,190 --> 00:16:57,050 Like let's say we wanted to create nobilities. 285 00:16:57,100 --> 00:16:58,340 That's really interesting. 286 00:16:58,540 --> 00:17:02,870 Let's give it a shot and say bar let's say abilities. 287 00:17:03,090 --> 00:17:04,500 Me a dictionary right. 288 00:17:04,540 --> 00:17:15,670 So the dictionary or the bill t's dictionary is going to be a dictionary of type string. 289 00:17:16,030 --> 00:17:23,110 And then what we're going to do is we're going to say an array and the array is going to be an array 290 00:17:23,110 --> 00:17:26,360 of what can be an array of dictionaries right. 291 00:17:26,620 --> 00:17:31,480 So let's see what it does here. 292 00:17:32,650 --> 00:17:35,190 Of type string and string. 293 00:17:35,200 --> 00:17:37,770 I'm just curious. 294 00:17:37,810 --> 00:17:40,000 The syntax is wrong here. 295 00:17:40,450 --> 00:17:47,810 But anyway my point here is you can have. 296 00:17:48,580 --> 00:17:52,620 You can have different items inside of your dictionaries. 297 00:17:52,630 --> 00:17:53,830 OK. 298 00:17:54,580 --> 00:18:03,200 Such as a boolean and in OK you can do all kinds of different things with your dictionaries. 299 00:18:03,200 --> 00:18:06,830 It doesn't have to just be strings and integers. 300 00:18:07,010 --> 00:18:10,250 So lots of cool stuff. 301 00:18:10,370 --> 00:18:12,320 This is just scratching the surface here. 302 00:18:12,350 --> 00:18:12,880 OK. 303 00:18:12,920 --> 00:18:17,360 Just touching the surface if you want to get a better synopsis of how dictionaries work again do that 304 00:18:17,360 --> 00:18:22,390 Google search I told you about how to hash tables work in computer science you can also look at Jason 305 00:18:22,390 --> 00:18:23,670 to start getting a feel. 306 00:18:23,700 --> 00:18:25,480 When I said Jaison That's J S. 307 00:18:25,520 --> 00:18:31,340 Oh and get a feel of how things work with with web and how it might translate to Swift. 308 00:18:31,820 --> 00:18:32,800 And that's it. 309 00:18:32,810 --> 00:18:34,240 Lots of good information. 310 00:18:34,400 --> 00:18:36,520 So get all in and let's move on and forward. 311 00:18:36,530 --> 00:18:39,020 Mark Price does slopes dotcom at CNN.