1 00:00:01,480 --> 00:00:02,870 A What's up everybody. 2 00:00:02,910 --> 00:00:09,120 Mark Price at Dev slopes dot com plugging our way through foundational swift and programming and not 3 00:00:09,120 --> 00:00:14,100 only teach India SWIP but I'm teaching the underlying core programming principles that you use with 4 00:00:14,100 --> 00:00:15,570 you in any programming language. 5 00:00:15,570 --> 00:00:17,250 So this is really good stuff. 6 00:00:17,250 --> 00:00:18,270 Take it in here. 7 00:00:18,300 --> 00:00:23,600 Go ahead and open up your X code 8 and we're going to get started with a playground. 8 00:00:23,820 --> 00:00:34,860 And this one we're going to call bulls not to be confused with like a bull with horns bulls and conditionals 9 00:00:35,370 --> 00:00:51,190 and comparison operators to create a folder for this swift and say boules and comparison's 10 00:00:53,740 --> 00:00:55,060 and create. 11 00:00:55,690 --> 00:01:00,510 So a boolean is true or false. 12 00:01:00,550 --> 00:01:05,640 Simple enough so far. 13 00:01:05,830 --> 00:01:07,210 We kind of done this once before. 14 00:01:07,210 --> 00:01:07,450 Right. 15 00:01:07,450 --> 00:01:09,540 Bar. 16 00:01:09,930 --> 00:01:18,220 Am I Am i the best teacher ever equals. 17 00:01:18,220 --> 00:01:18,840 What's that. 18 00:01:20,200 --> 00:01:21,330 Jennifer says true. 19 00:01:21,400 --> 00:01:22,480 Thanks Jennifer. 20 00:01:22,480 --> 00:01:22,780 OK. 21 00:01:22,780 --> 00:01:24,590 So am I the best teacher ever. 22 00:01:25,060 --> 00:01:25,840 Well thank you. 23 00:01:25,960 --> 00:01:30,620 I wouldn't say that about myself because there will be narcissistic. 24 00:01:30,730 --> 00:01:31,600 So that's a boolean. 25 00:01:31,660 --> 00:01:32,430 It's true. 26 00:01:32,650 --> 00:01:37,190 And you know but it can also be false can't be anything else so. 27 00:01:37,480 --> 00:01:39,320 So am I the best teacher ever. 28 00:01:39,330 --> 00:01:45,940 Well let's say the ExCo just keeps crashing and you're getting sick of watching me have X code crash 29 00:01:46,150 --> 00:01:47,180 and you're just angry. 30 00:01:47,230 --> 00:01:53,860 And so now you want to set this to false because it's not my fault it is crashing. 31 00:01:53,860 --> 00:01:56,530 Don't get on my case don't get on my case. 32 00:01:56,530 --> 00:01:58,350 So am I the best teacher ever. 33 00:01:58,600 --> 00:02:06,670 I'm no longer the best teacher ever because this is up to us and you know I actually do cut out a lot 34 00:02:06,670 --> 00:02:12,760 of the a lot of the crashes but I leave some of them in there so you can know that again real life development 35 00:02:13,240 --> 00:02:14,500 you see in the flesh there. 36 00:02:14,500 --> 00:02:18,020 So am I the best teacher ever is now false because it keeps crashing. 37 00:02:18,070 --> 00:02:20,520 OK and I'm not cutting it out of the video. 38 00:02:21,250 --> 00:02:21,780 OK. 39 00:02:21,970 --> 00:02:23,830 Anyway so true or false. 40 00:02:23,860 --> 00:02:24,530 So what does that mean. 41 00:02:24,540 --> 00:02:24,950 Why does it. 42 00:02:24,970 --> 00:02:28,550 Why does it mean that we are storing a very true or false variable. 43 00:02:28,960 --> 00:02:35,080 Well the funny thing is actually most of the time you're not storing true or false values in a variable. 44 00:02:35,140 --> 00:02:38,490 You will and I do it frequently but not all the time. 45 00:02:38,680 --> 00:02:48,460 Boolean values are sometimes more so used to just compare things or to to do something based on some 46 00:02:48,460 --> 00:02:49,290 condition. 47 00:02:49,530 --> 00:02:50,940 OK. 48 00:02:51,400 --> 00:02:51,670 Right. 49 00:02:51,670 --> 00:02:54,190 Does that make any sense you want to do something based. 50 00:02:54,220 --> 00:02:55,030 Should I do this. 51 00:02:55,030 --> 00:03:01,960 You know if you know when you were a kid remember when you were a kid and your parents were like Yo 52 00:03:02,200 --> 00:03:07,510 if you clean your room and do your chores we're going to go to Disneyland otherwise I'm going to take 53 00:03:07,510 --> 00:03:10,020 this big black belt with these spikes on it. 54 00:03:10,030 --> 00:03:15,520 I'm going to beat you a rough childhood anyway. 55 00:03:15,890 --> 00:03:17,890 Cause and effect or true or false. 56 00:03:18,110 --> 00:03:21,000 Is a foundational principle for that. 57 00:03:21,700 --> 00:03:27,250 And this is again type inference here we're inferring it as a bull but the actual key word if you want 58 00:03:27,250 --> 00:03:30,470 to explicitly declare it is bull. 59 00:03:30,550 --> 00:03:30,960 OK. 60 00:03:31,030 --> 00:03:32,580 Not bullying. 61 00:03:32,830 --> 00:03:33,860 OK. 62 00:03:33,880 --> 00:03:37,990 Not bullying literal type convert what nothing else OK just bull and I'm not going explain what these 63 00:03:38,110 --> 00:03:38,520 things are. 64 00:03:38,520 --> 00:03:42,970 If you're wondering what's the difference between bullying bullying and swift on the part when them 65 00:03:43,180 --> 00:03:44,280 autocomplete comes up. 66 00:03:44,350 --> 00:03:45,900 Go search on Google. 67 00:03:45,940 --> 00:03:47,970 I'm telling you all you need to do is blog. 68 00:03:48,190 --> 00:03:48,930 OK. 69 00:03:49,270 --> 00:03:50,730 So true or false. 70 00:03:50,830 --> 00:03:52,180 And how can you use these things. 71 00:03:52,180 --> 00:03:52,510 Well 72 00:03:56,470 --> 00:03:57,560 to make decisions for you. 73 00:03:57,560 --> 00:04:00,740 So that's it. 74 00:04:00,820 --> 00:04:02,150 That's bull. 75 00:04:02,830 --> 00:04:03,920 Let's put them in action. 76 00:04:03,940 --> 00:04:08,900 Let's actually see how we can use comparisons with. 77 00:04:09,250 --> 00:04:10,990 Well I can say one more thing actually. 78 00:04:11,440 --> 00:04:12,330 Just one more thing. 79 00:04:12,430 --> 00:04:13,210 OK. 80 00:04:13,570 --> 00:04:15,850 Just to blow your mind confuse you completely. 81 00:04:16,120 --> 00:04:30,490 If true equals false or if true equals true print WDF this is what the fish. 82 00:04:30,490 --> 00:04:31,810 By the way. 83 00:04:31,810 --> 00:04:33,710 All right. 84 00:04:34,060 --> 00:04:35,310 What's going on here. 85 00:04:35,710 --> 00:04:39,670 So we're using the double equals sign here. 86 00:04:39,670 --> 00:04:43,280 This is a comparison operator and this is called equal to. 87 00:04:43,360 --> 00:04:47,200 So if true is equal to false. 88 00:04:47,260 --> 00:04:48,080 OK. 89 00:04:48,670 --> 00:04:53,030 If true or false then this whole side of the equation would be true but it's not. 90 00:04:53,030 --> 00:05:01,420 So this whole side of the equation is false so we're saying if false or OK this is the or OPERATOR OK 91 00:05:02,590 --> 00:05:06,260 and or if true equals true. 92 00:05:06,400 --> 00:05:10,440 So if this is true or if this is true then go into here. 93 00:05:10,900 --> 00:05:11,500 OK. 94 00:05:11,650 --> 00:05:13,270 So true is definitely equal to true. 95 00:05:13,270 --> 00:05:16,540 So this is going to return the entire section over here to true. 96 00:05:16,840 --> 00:05:24,490 And so again you can start to see maybe how you can start comparing things in your code. 97 00:05:24,790 --> 00:05:31,180 And this is a great example because you probably wouldn't write this in your code but a lot of coding 98 00:05:31,180 --> 00:05:36,600 tests and brainteasers out there will actually ask you to decide for things like this. 99 00:05:36,610 --> 00:05:40,290 So you're you can they can see how your brain works and see if you can read the code. 100 00:05:40,420 --> 00:05:42,480 This is really good for learning how to read code. 101 00:05:42,610 --> 00:05:43,060 OK. 102 00:05:43,150 --> 00:05:45,080 So true or false. 103 00:05:45,460 --> 00:05:52,390 You know a better example is for instance var has data finished downloading. 104 00:05:52,390 --> 00:05:57,860 You know how when you get an app and there's a spinner bar was explicitly declare it. 105 00:05:58,150 --> 00:05:59,610 So you know it's a boolean. 106 00:05:59,620 --> 00:06:04,150 So basically when you get that spinner bar it's hitting up a server and it's downloading data. 107 00:06:04,150 --> 00:06:04,710 OK. 108 00:06:04,870 --> 00:06:08,410 So you know we've got the spinner and dot dot dot you know. 109 00:06:08,720 --> 00:06:10,100 Little color that was nice. 110 00:06:10,100 --> 00:06:12,040 Got. 111 00:06:12,640 --> 00:06:14,250 That's funny. 112 00:06:14,240 --> 00:06:14,910 Let's just pick a car. 113 00:06:14,920 --> 00:06:17,370 I don't know what it's doing to be honest but I like it. 114 00:06:19,580 --> 00:06:22,110 It's a feature of a feature of the playgrounds anyway. 115 00:06:22,130 --> 00:06:27,200 So we're downloading data from the internet then after it's done downloading we can say has data finished 116 00:06:27,200 --> 00:06:29,080 downloading equals true. 117 00:06:29,210 --> 00:06:29,730 All right. 118 00:06:29,870 --> 00:06:35,640 And then we can do something like no load UI and other features. 119 00:06:35,960 --> 00:06:42,380 So this is an example of when you actually use a ball in your code and in your projects with for things 120 00:06:42,380 --> 00:06:48,130 like this and I've done things like this before it's nothing wrong with it it's a common thing to do. 121 00:06:48,160 --> 00:06:48,830 So it's boolean. 122 00:06:48,830 --> 00:06:49,930 True or false. 123 00:06:49,940 --> 00:06:56,570 It's one way you can use it again anytime anytime you need to get a true false yes or no Bullen's the 124 00:06:56,570 --> 00:07:05,180 way to go for short the bulls go hand in hand or boolean logic goes hand in hand with comparison operators 125 00:07:05,330 --> 00:07:08,980 now can comparison operators will return a boolean. 126 00:07:10,010 --> 00:07:10,470 OK. 127 00:07:10,550 --> 00:07:16,700 When I say and it is bull but bullying is a long term for it with just condense it here. 128 00:07:16,690 --> 00:07:32,250 So for instance this is really easy if one is equal to two print should not see this. 129 00:07:33,980 --> 00:07:36,630 So will never be executed. 130 00:07:36,650 --> 00:07:37,630 Thank you. 131 00:07:37,640 --> 00:07:38,450 It's smart. 132 00:07:38,510 --> 00:07:39,910 So if one equals two. 133 00:07:40,070 --> 00:07:42,290 Well one is not equal to two in the recall. 134 00:07:42,290 --> 00:07:44,300 So again this returns a boolean. 135 00:07:44,610 --> 00:07:45,130 OK. 136 00:07:45,350 --> 00:07:46,570 That's really interesting huh. 137 00:07:46,910 --> 00:07:49,150 I wonder do you think you could do something like that over here. 138 00:07:49,160 --> 00:07:52,490 Actually an in a in a boolean itself. 139 00:07:52,500 --> 00:07:59,570 So what if we said instead of saying false we'll say Well said This has data finished downloading equals 140 00:07:59,660 --> 00:08:01,010 one equals two 141 00:08:04,000 --> 00:08:05,710 interesting. 142 00:08:05,710 --> 00:08:09,790 So like I said this is returning a boolean true or false value that's been stored in here. 143 00:08:09,790 --> 00:08:16,060 So like I was telling you earlier if you use them less here and variables and you use them more in conditional 144 00:08:16,060 --> 00:08:16,750 logic. 145 00:08:16,930 --> 00:08:17,720 OK. 146 00:08:18,020 --> 00:08:22,720 They return them but only return a boolean for the sake of performing. 147 00:08:22,720 --> 00:08:23,900 Making a decision. 148 00:08:24,180 --> 00:08:24,450 OK. 149 00:08:24,460 --> 00:08:30,250 So if one equals to print you should see this if two equals two. 150 00:08:30,250 --> 00:08:31,090 Now we're seeing it. 151 00:08:31,180 --> 00:08:31,760 OK. 152 00:08:32,100 --> 00:08:38,810 So it returns a true or false value conditional conditional logic. 153 00:08:38,810 --> 00:08:39,070 OK. 154 00:08:39,080 --> 00:08:40,860 So let's talk about the different operators here. 155 00:08:40,970 --> 00:08:41,460 All right. 156 00:08:41,780 --> 00:08:46,770 So we've got equal to and it's the equal sign. 157 00:08:47,150 --> 00:08:56,680 We've got not equal to which is the exclamation point and the equal sign not equal to. 158 00:08:56,690 --> 00:09:04,250 All right we've got greater then and this is you know a that's greater than B. 159 00:09:04,520 --> 00:09:07,120 So I say that's greater then. 160 00:09:07,160 --> 00:09:09,740 And I forgot my call and be consistent. 161 00:09:10,280 --> 00:09:20,280 And then we've got greater greater than or equal to which is you know the big Pacman mouth to the left 162 00:09:20,500 --> 00:09:26,680 equal to and then we have less than or equal to 163 00:09:29,670 --> 00:09:30,580 like so. 164 00:09:31,170 --> 00:09:34,820 And then we've got less than two. 165 00:09:35,030 --> 00:09:35,360 OK. 166 00:09:35,460 --> 00:09:39,710 So obviously there's a lot going on here but let's see how it actually works. 167 00:09:39,770 --> 00:09:40,650 Let's see it in action. 168 00:09:40,650 --> 00:09:41,140 OK. 169 00:09:41,460 --> 00:09:48,330 So you know of course the common example here that we've used already is a bank account so we can obviously 170 00:09:48,330 --> 00:09:58,950 do that here again so our bank balance right equals are equals five $400 gave our item to buy equals 171 00:09:59,080 --> 00:10:00,150 $100. 172 00:10:00,350 --> 00:10:01,140 OK. 173 00:10:01,370 --> 00:10:09,930 So then what we can do is we can say if bank balance bank balance is greater than or equal to item to 174 00:10:09,930 --> 00:10:16,320 buy Why wouldn't we just say if it's greater then well the buyer was $400 this would turn out to be 175 00:10:16,320 --> 00:10:17,790 false and we would be able to buy it. 176 00:10:17,790 --> 00:10:18,610 That's not right. 177 00:10:18,630 --> 00:10:23,670 We need to be able to go to zero dollars in our account but not into the negative unless you turn unless 178 00:10:23,670 --> 00:10:26,480 you put an overdraft protection you know which. 179 00:10:26,520 --> 00:10:27,820 Why did people do that. 180 00:10:27,840 --> 00:10:29,060 No frigging clue. 181 00:10:29,070 --> 00:10:30,000 Just what I wanted to do. 182 00:10:30,000 --> 00:10:36,830 I wanted to spend money I didn't have get the item and then have you charge me a negative fee. 183 00:10:36,840 --> 00:10:40,500 I mean I guess if you want to be embarrassed at the register because your card didn't go through and 184 00:10:40,500 --> 00:10:43,780 you're like I'm sorry sir your card didn't go through Was everything OK. 185 00:10:43,800 --> 00:10:46,580 Do you need any help with your family. 186 00:10:46,620 --> 00:10:47,340 No. 187 00:10:47,400 --> 00:10:53,300 So anyway my point is we need the equal sign so we can actually buy that item the item to buy. 188 00:10:53,980 --> 00:10:54,450 OK. 189 00:10:54,660 --> 00:10:57,480 Then print purchased item. 190 00:10:57,690 --> 00:10:58,480 OK. 191 00:10:58,500 --> 00:11:05,250 So if you've got more money or equal to or an equal amount of money I'd buy print purchase item. 192 00:11:05,280 --> 00:11:15,930 Another thing we could do you know we could say if item to buy is greater than the bank balance 193 00:11:19,100 --> 00:11:23,030 you need more money. 194 00:11:23,760 --> 00:11:24,470 OK. 195 00:11:24,710 --> 00:11:25,130 So 196 00:11:28,350 --> 00:11:32,490 if Ireland buy is great for the balance you need more money for this and we're using a greater than 197 00:11:32,490 --> 00:11:33,090 only sign. 198 00:11:33,120 --> 00:11:36,940 So let's say that having to buy is now five hundred dollars. 199 00:11:37,800 --> 00:11:39,450 Sure enough it prints out right here. 200 00:11:39,690 --> 00:11:43,140 OK this is cool so so far we've used greater than or equal to. 201 00:11:43,260 --> 00:11:47,460 We've also used the greater than sign here. 202 00:11:47,710 --> 00:11:48,560 OK. 203 00:11:48,690 --> 00:11:58,440 And maybe maybe your bank whenever you whenever you hit zero for instance it wants to give you a notification 204 00:11:58,440 --> 00:12:01,600 saying hey you're in no money you spend it all. 205 00:12:01,600 --> 00:12:08,900 You know so you know this is a silly example but we can say if item to buy is equal to bank balance. 206 00:12:09,060 --> 00:12:10,110 OK. 207 00:12:10,280 --> 00:12:19,750 And then what we can do is we can say print Hey buddy your balance is now zero. 208 00:12:20,240 --> 00:12:21,090 OK. 209 00:12:21,210 --> 00:12:28,580 So I'd advise the bank balance Hey buddy your balance is now zero so if I say I'm the buy is $400. 210 00:12:29,340 --> 00:12:30,720 Hey buddy your balance is now zero. 211 00:12:30,720 --> 00:12:35,730 So if this is equal to this OK then do this. 212 00:12:35,730 --> 00:12:42,680 Now remember remember these operators here OK are returning a true or false value. 213 00:12:42,930 --> 00:12:43,230 OK. 214 00:12:43,230 --> 00:12:46,300 So remember you could actually store this in a variable. 215 00:12:46,350 --> 00:12:55,890 So for instance var am I at zero equals I want to buy people's bank balance. 216 00:12:55,930 --> 00:12:56,210 OK. 217 00:12:56,220 --> 00:13:01,410 So it's going to run this operation first and then what it's going to do is it's going to return a true 218 00:13:01,410 --> 00:13:02,910 or false value into this. 219 00:13:02,910 --> 00:13:03,680 And this is a bull. 220 00:13:03,690 --> 00:13:06,050 And so you can actually store the result if you want it to. 221 00:13:06,060 --> 00:13:08,860 But again like I said in most cases you don't. 222 00:13:08,870 --> 00:13:09,630 OK. 223 00:13:09,780 --> 00:13:13,010 And then let's see here. 224 00:13:13,020 --> 00:13:20,190 The only other one of great importance is the not equal to sign so I'll show you that as well to friends 225 00:13:20,190 --> 00:13:23,300 and also we want to compare instead of numbers we want to compare strings. 226 00:13:23,520 --> 00:13:38,420 So if let's say correct spelling is not equal to. 227 00:13:38,670 --> 00:13:47,090 And let's actually let's better save our word one equals Let's get say let's say this are book titles. 228 00:13:47,130 --> 00:14:07,520 So book title one equals let's say Harry Potter and the Moffit of Mier on my book. 229 00:14:07,830 --> 00:14:08,070 OK. 230 00:14:08,070 --> 00:14:14,670 Anyway and then we have a book titled two equals unless we have the same thing here but this one's entered 231 00:14:14,670 --> 00:14:15,580 by a user. 232 00:14:15,630 --> 00:14:18,760 OK this one was entered by a user they knew would be the same thing right. 233 00:14:18,990 --> 00:14:23,430 So let's say that the user action in lowercase this and you know if you got the A. 234 00:14:23,550 --> 00:14:24,930 You know this bad spelling. 235 00:14:24,930 --> 00:14:38,910 So we can do is we can say if Book Title One is not equal to book title to you know print need to fix 236 00:14:38,910 --> 00:14:42,980 spelling before printing whatever. 237 00:14:43,600 --> 00:14:44,080 OK. 238 00:14:44,370 --> 00:14:48,920 So if this one is not the same as this one then do something else. 239 00:14:48,930 --> 00:14:49,650 OK. 240 00:14:49,910 --> 00:14:53,810 So it's basically the opposite of using these here. 241 00:14:53,820 --> 00:14:54,070 OK. 242 00:14:54,090 --> 00:14:57,100 And you can you'll see programmers use these interchangeably. 243 00:14:57,150 --> 00:15:02,640 And you can kind of sometimes you can do to get the same result in decision using different operators 244 00:15:02,820 --> 00:15:05,020 just depending on what you put first or second. 245 00:15:05,040 --> 00:15:08,260 But you can do whatever one you want which is cool. 246 00:15:08,260 --> 00:15:09,830 So this is all really cool. 247 00:15:09,870 --> 00:15:13,680 This is really cool stuff. 248 00:15:13,680 --> 00:15:19,910 Another thing you can do is remember how we did this example up here has data finish downloading. 249 00:15:19,970 --> 00:15:29,040 You can also use that unary operators so we could say if our first let's let's do it with stood up here 250 00:15:30,270 --> 00:15:31,860 before it's been set to true. 251 00:15:31,920 --> 00:15:38,040 So if not has data finished downloading. 252 00:15:38,460 --> 00:15:44,840 OK then print loading data. 253 00:15:45,630 --> 00:15:50,850 So at this point in time if the data has not finished downloading let's print to the screen loading 254 00:15:50,850 --> 00:15:51,120 data. 255 00:15:51,120 --> 00:15:56,490 So this is the operator put before the boolean value. 256 00:15:56,490 --> 00:15:57,990 And so it's saying the opposite right. 257 00:15:58,020 --> 00:16:03,780 So that's why it's so important to word your variables with your Bulleen so carefully so has data finish 258 00:16:03,780 --> 00:16:04,340 downloading. 259 00:16:04,350 --> 00:16:05,490 That's the question we're asking. 260 00:16:05,490 --> 00:16:09,660 So if the data has not finished eling that's what this is saying here. 261 00:16:09,660 --> 00:16:10,760 Print this here. 262 00:16:10,960 --> 00:16:13,140 OK print loading data. 263 00:16:13,140 --> 00:16:14,430 Pretty cool stuff right. 264 00:16:14,430 --> 00:16:18,120 So what we've done here so far is we've just used some of the basic operators of course we've used the 265 00:16:18,120 --> 00:16:20,900 greater than or equal to you can also use the less than or equal to. 266 00:16:20,970 --> 00:16:26,370 And you can start making decisions based on those operators. 267 00:16:26,370 --> 00:16:32,690 OK the result of those operators which is I think pretty dang cool. 268 00:16:32,700 --> 00:16:35,940 One more thing I want to show you and then we'll be done. 269 00:16:35,940 --> 00:16:40,020 So if book A 1 is not what the book title to. 270 00:16:40,590 --> 00:16:44,500 OK then we need to fix spelling before printing great else. 271 00:16:44,600 --> 00:16:45,450 Here's the key word. 272 00:16:45,450 --> 00:16:49,000 So if this happens or if this is true great. 273 00:16:49,020 --> 00:16:54,590 If not go to the next block of code and this will always always always be executed. 274 00:16:54,750 --> 00:17:02,160 If this is false and this will never ever ever be executed if this is true it very important to know. 275 00:17:02,400 --> 00:17:08,510 And so you say print book looks great send to printer. 276 00:17:09,740 --> 00:17:11,170 Pretty cool. 277 00:17:12,410 --> 00:17:13,270 Put her on. 278 00:17:13,290 --> 00:17:19,630 It's not what the book title too great we can do more though like we can also say so. 279 00:17:19,700 --> 00:17:24,060 If so the first thing we want to do is check the spelling then what we want to do is we want to make 280 00:17:24,060 --> 00:17:28,740 sure that the size of the book title is a proper size what we can say. 281 00:17:28,740 --> 00:17:30,080 Else if. 282 00:17:30,080 --> 00:17:30,770 OK. 283 00:17:30,870 --> 00:17:37,410 Book Title One dot see her length on the string here. 284 00:17:41,040 --> 00:17:41,610 See 285 00:17:53,690 --> 00:18:04,020 and far here oh characters has the string and the characters and the cat her goodness so if the count 286 00:18:04,050 --> 00:18:13,710 of the entire string is greater then let's say 10 like then we need to do is print find a new title 287 00:18:13,710 --> 00:18:15,170 for the book. 288 00:18:16,080 --> 00:18:16,700 OK. 289 00:18:17,340 --> 00:18:18,690 So that's interesting. 290 00:18:18,690 --> 00:18:24,710 So look what we did here in the book one title or the book title one is not equal to book title to them 291 00:18:24,710 --> 00:18:26,490 we need to send us the printing. 292 00:18:26,490 --> 00:18:27,880 Well let's say that we fixed it. 293 00:18:27,900 --> 00:18:29,730 All right so this is great we've just fixed it. 294 00:18:29,730 --> 00:18:34,400 The book is now perfectly edited whatever. 295 00:18:34,560 --> 00:18:35,520 But look here. 296 00:18:35,520 --> 00:18:37,450 Find a new title for your book is now called. 297 00:18:37,470 --> 00:18:38,020 OK. 298 00:18:38,280 --> 00:18:40,740 So we passed the first one this is true. 299 00:18:40,800 --> 00:18:47,380 So then we go to the next thing or excuse me this is false and therefore it's not called. 300 00:18:47,610 --> 00:18:48,600 This is false. 301 00:18:48,600 --> 00:18:56,250 So ELSE IF book titled two characters that count is greater than 10 oh no we need to find a new title 302 00:18:56,250 --> 00:18:56,570 for the book. 303 00:18:56,570 --> 00:18:58,280 This is too long it's not going to fit on the book. 304 00:18:58,500 --> 00:19:04,860 OK so we need a book that has nine characters in order in order to get to here to the else clause so 305 00:19:05,430 --> 00:19:10,930 let's say one two three four five count the space that the character six seven eight nine. 306 00:19:11,080 --> 00:19:18,160 Oh wow so Harry Potter and the muppet of fire was ternary below. 307 00:19:18,290 --> 00:19:24,870 There's books about anymore but the editors thought it might be a little more appropriate to add a G 308 00:19:24,870 --> 00:19:25,480 there instead. 309 00:19:25,480 --> 00:19:32,400 So we've got some crazy book that we've released the title on and now look see if we pass it here. 310 00:19:32,400 --> 00:19:37,220 So if book titled to the characters that count is greater than 10. 311 00:19:37,350 --> 00:19:43,650 Print a new title for the book and of course we need to copy this over here because it needs to be the 312 00:19:43,650 --> 00:19:45,530 same. 313 00:19:46,190 --> 00:19:49,170 So a book title is not equal to a book title to. 314 00:19:49,200 --> 00:19:53,370 Well it is so this is false we're not going to call this LCF book title that characters that count is 315 00:19:53,370 --> 00:19:54,380 greater than 10. 316 00:19:54,420 --> 00:19:56,080 We fix that problem too. 317 00:19:56,100 --> 00:19:57,660 So this isn't going to be false. 318 00:19:57,780 --> 00:20:03,420 So here's the end all catch all so once we pass those conditions it is now true and we're able to print 319 00:20:03,420 --> 00:20:04,040 the book. 320 00:20:04,190 --> 00:20:04,460 OK. 321 00:20:04,470 --> 00:20:08,390 So we work with if statements else if statements else statements. 322 00:20:08,390 --> 00:20:12,020 We've worked with these conditional operators here. 323 00:20:12,140 --> 00:20:12,590 OK. 324 00:20:12,620 --> 00:20:15,360 That double equals the greater than the greater than equal to. 325 00:20:15,360 --> 00:20:20,960 We've also talked about less and less than or equal to we know a lot of stuff here. 326 00:20:21,030 --> 00:20:25,840 We've talked about the urinary not OPERATOR OK the prefix here. 327 00:20:26,010 --> 00:20:33,030 If it's not finished downloading we're talking about booleans and true and false and how this will equate 328 00:20:33,030 --> 00:20:34,860 to a true or false. 329 00:20:34,890 --> 00:20:36,740 Some really good stuff so we're going to call this video done. 330 00:20:36,740 --> 00:20:37,680 It's a lot to take in. 331 00:20:37,680 --> 00:20:43,770 Watch it again and you're going to start using conditions in your applications because that's how applications 332 00:20:43,870 --> 00:20:48,870 think and make decisions is by using tools. 333 00:20:49,000 --> 00:20:51,410 Mark Price Loeb's dotcom. 334 00:20:51,460 --> 00:20:52,630 Moving on and for.