1 00:00:01,190 --> 00:00:02,520 What's up my peeps. 2 00:00:02,520 --> 00:00:06,920 Mark Price you're at slow dot com in case you've forgotten. 3 00:00:07,020 --> 00:00:09,530 And hear new stuff and to my courses. 4 00:00:09,660 --> 00:00:11,390 You're going to hear that a lot. 5 00:00:11,550 --> 00:00:12,030 That's OK. 6 00:00:12,030 --> 00:00:14,080 You're going to learn to love it. 7 00:00:14,350 --> 00:00:16,950 It has some people who are like oh this rock and roll music. 8 00:00:16,950 --> 00:00:17,770 It's driving me crazy. 9 00:00:17,770 --> 00:00:19,440 You do it over and over and over again. 10 00:00:19,590 --> 00:00:22,500 But then everyone else is like this is so cool. 11 00:00:22,590 --> 00:00:26,430 It gets me motivated gets me excited gets the energy going because most of you guys are like doing this 12 00:00:26,430 --> 00:00:27,720 after work at night time. 13 00:00:27,720 --> 00:00:29,360 I'm doing a here near midnight. 14 00:00:29,400 --> 00:00:32,600 You've got to have something to wake you up and excite you about coding. 15 00:00:32,610 --> 00:00:36,150 If you find coding boring it doesn't have to be. 16 00:00:36,150 --> 00:00:36,780 OK. 17 00:00:37,080 --> 00:00:42,570 So that's my inspiration for the hour of course of course is this lesson is going to be that long. 18 00:00:42,570 --> 00:00:45,110 I hope we are going to go ahead and get started with the playground. 19 00:00:45,120 --> 00:00:51,690 And today we're going to finish our discussion on making conditional decisions and we're going to talk 20 00:00:51,690 --> 00:00:53,550 about logical operators today. 21 00:00:53,550 --> 00:00:57,460 We've talked about booleans right we've talked about if statements and statements. 22 00:00:57,900 --> 00:00:59,850 Those are called conditionals. 23 00:00:59,850 --> 00:01:04,520 Now we're going to talk about logical operators so logical operators. 24 00:01:04,520 --> 00:01:05,230 All right. 25 00:01:05,280 --> 00:01:09,260 Next time you go out on a date this this is what I want you to do. 26 00:01:09,300 --> 00:01:13,360 Be like hey you want to see my logical operators. 27 00:01:13,450 --> 00:01:18,460 Your day is going to be like this guy's awesome and this girl's cool. 28 00:01:19,050 --> 00:01:20,690 Serious do it all the time. 29 00:01:20,700 --> 00:01:21,740 All right. 30 00:01:23,360 --> 00:01:24,950 Don't do that. 31 00:01:24,950 --> 00:01:25,190 All right. 32 00:01:25,190 --> 00:01:25,730 Here we go. 33 00:01:25,730 --> 00:01:31,720 So I'm going to go here into our bulls and comparisons. 34 00:01:31,890 --> 00:01:37,660 Well call this logical operators a new folder. 35 00:01:37,660 --> 00:01:38,570 Here we go. 36 00:01:39,110 --> 00:01:39,380 OK. 37 00:01:39,380 --> 00:01:42,440 So again we've talked about true and false and everything else. 38 00:01:42,500 --> 00:01:49,130 Let's talk about how to make decisions and more decisions how to make more better decisions and one 39 00:01:49,130 --> 00:01:53,160 more I wanted to reemphasize on was that your unary operator. 40 00:01:53,270 --> 00:01:55,590 It's also a logical NOT operator. 41 00:01:55,610 --> 00:01:59,640 If that makes any sense so logical NOT operator. 42 00:01:59,800 --> 00:02:01,340 Sexually the way you say it. 43 00:02:01,670 --> 00:02:09,660 It's also a urinary a urinary prefix operator. 44 00:02:09,890 --> 00:02:12,920 Again those are just some terms for you there. 45 00:02:13,070 --> 00:02:14,330 So what is that. 46 00:02:14,330 --> 00:02:24,540 Well let me say allowed entry equals false and you. 47 00:02:24,630 --> 00:02:26,270 Like giving us an air. 48 00:02:26,420 --> 00:02:28,180 And so let what does it let. 49 00:02:28,220 --> 00:02:34,570 Let is a constant It means it cannot be changed so I cannot say allowed entry equals true. 50 00:02:34,700 --> 00:02:38,990 OK so you've got variables and you've got constants one you can change one you can't change it's all 51 00:02:38,990 --> 00:02:39,880 you've got to know about it. 52 00:02:39,960 --> 00:02:40,950 Pretty simple. 53 00:02:41,090 --> 00:02:45,520 OK so loud and true equals false. 54 00:02:45,550 --> 00:02:47,510 You can't get in right you can't get in the building. 55 00:02:47,540 --> 00:02:55,370 So if not allowed entry print access denied. 56 00:02:55,380 --> 00:03:03,020 All right so logical operator what it's really saying is it's the opposite of this. 57 00:03:03,020 --> 00:03:05,960 More or less so if allowed entry is true. 58 00:03:05,960 --> 00:03:10,850 Well we're not ask we're not doing that check we're saying if allowed entry is not true. 59 00:03:10,850 --> 00:03:15,790 So this would be the exact same thing as writing if allowed entry is not equal to true. 60 00:03:15,800 --> 00:03:19,050 That's the exact same thing except this is a little more writing right. 61 00:03:19,060 --> 00:03:24,410 One two three four five six different characters that you have to write are actually five more characters 62 00:03:24,410 --> 00:03:28,380 than you'd need to write on there plus the space anyway and it's long. 63 00:03:28,460 --> 00:03:32,540 So when you become a more veteran programmer you're going to start using this a lot more. 64 00:03:32,540 --> 00:03:37,760 Sometimes it makes sense to say this when you're new because it's easier to read ok and go ahead and 65 00:03:37,760 --> 00:03:38,490 do it from now on. 66 00:03:38,510 --> 00:03:40,250 You can feel free to do this. 67 00:03:40,340 --> 00:03:49,430 It's not equal to true but that the not operator is a quick shorthand way to say not OK if this is not 68 00:03:49,520 --> 00:03:50,090 true. 69 00:03:50,260 --> 00:03:51,060 OK. 70 00:03:51,640 --> 00:03:52,640 So that makes sense. 71 00:03:52,720 --> 00:03:56,200 OK just re-emphasizing that you're going to see a lot in other people's code. 72 00:03:57,250 --> 00:03:58,180 A step further. 73 00:03:58,340 --> 00:03:59,140 OK. 74 00:03:59,510 --> 00:04:04,220 Let again Constance you always want to use constants whenever you're not going to change the value if 75 00:04:04,220 --> 00:04:08,200 you are going to change the value is a variable but if you know you're not going to change the value 76 00:04:08,380 --> 00:04:10,540 is a constant memory optimized. 77 00:04:10,560 --> 00:04:12,640 Ok so very important use constants. 78 00:04:12,640 --> 00:04:16,300 At all possible entered door code. 79 00:04:16,330 --> 00:04:17,430 Oh OK. 80 00:04:17,450 --> 00:04:20,330 Now we're entering a door code equals true. 81 00:04:20,780 --> 00:04:21,610 OK. 82 00:04:21,860 --> 00:04:27,770 And let's say there's also a retina scan like it's like Metal Gear Solid OK. 83 00:04:28,070 --> 00:04:31,320 Past retina scan which was false. 84 00:04:31,340 --> 00:04:37,400 You know some high tech stuff you know or that game you'd like go and then back the original very first 85 00:04:37,400 --> 00:04:37,910 one. 86 00:04:37,910 --> 00:04:39,050 Is this the cause of the mall. 87 00:04:39,050 --> 00:04:43,910 I think you go knock on the crate and the really dumb AI would come running around and then after they 88 00:04:43,910 --> 00:04:46,940 felt like the noise was no longer threatening you know they would just chill 89 00:04:49,820 --> 00:04:50,840 it's irrelevant. 90 00:04:51,070 --> 00:04:51,660 OK. 91 00:04:51,780 --> 00:04:55,410 When it's midnight when you're making videos at midnight you can say whatever you want. 92 00:04:55,500 --> 00:05:01,020 And when you've got all these people watching you it's how it's going to be. 93 00:05:01,310 --> 00:05:03,240 Try and stop me. 94 00:05:03,240 --> 00:05:05,470 Camera isn't even here. 95 00:05:05,490 --> 00:05:13,020 Maybe if you we're here we're going to do is some We're going to use logical operators to make some 96 00:05:13,020 --> 00:05:19,170 decisions so let's say we want the user or the person is coming in to enter the door code and pass the 97 00:05:19,170 --> 00:05:20,830 retina scan. 98 00:05:20,970 --> 00:05:29,420 So what we're going to do is we're going to say if entered door code and past retinal scan. 99 00:05:29,850 --> 00:05:34,630 OK we're going to print welcome however. 100 00:05:34,890 --> 00:05:36,050 However. 101 00:05:36,120 --> 00:05:38,030 OK. 102 00:05:39,780 --> 00:05:45,120 Remember the movie Mission Impossible like they're reviewing You know the CIA bunker and how to get 103 00:05:45,120 --> 00:05:49,080 in the guy has to go through all the steps of the retinal scan they knew that they couldn't do it. 104 00:05:49,080 --> 00:05:50,660 So this is the way you do it. 105 00:05:50,700 --> 00:05:56,170 You enter door code and you do a retinal scan but so I say let. 106 00:05:56,610 --> 00:06:03,050 I am Tom Cruise from Mission Impossible. 107 00:06:03,240 --> 00:06:13,800 So if entered door code and past retina scan or if I am Tom Cruise for Mission Impossible then we can 108 00:06:13,800 --> 00:06:15,690 get in print welcome and sure enough. 109 00:06:15,690 --> 00:06:20,650 Mission Impossible Tom Cruise is in the door but of course I am not Tom Cruise. 110 00:06:20,830 --> 00:06:24,110 So this is what is this here. 111 00:06:24,110 --> 00:06:30,800 This is the logical or OPERATOR OK so what's going to happen is the right side is going to be calculated 112 00:06:30,800 --> 00:06:31,470 first here. 113 00:06:31,640 --> 00:06:33,530 OK. 114 00:06:33,530 --> 00:06:34,280 All right. 115 00:06:34,280 --> 00:06:40,050 And so if this is true OK it's going to be this or operator and then it doesn't even care about this. 116 00:06:40,280 --> 00:06:43,790 If this is true because or means one or the other has to be true. 117 00:06:43,850 --> 00:06:45,330 So this side's going to get run. 118 00:06:45,500 --> 00:06:49,500 And if that's true great otherwise or let's run this and then we do. 119 00:06:49,730 --> 00:06:52,240 If this is true and if this is true. 120 00:06:52,370 --> 00:06:52,690 OK. 121 00:06:52,700 --> 00:06:53,880 So then we. 122 00:06:53,990 --> 00:06:58,370 So we're at what we're saying here is hey both of these have to be true using the and operator here. 123 00:06:58,370 --> 00:07:00,360 So this is or this is. 124 00:07:00,390 --> 00:07:01,610 And OK. 125 00:07:01,760 --> 00:07:04,340 This is why it was printing when he was Tom Cruise. 126 00:07:04,340 --> 00:07:06,170 Right. 127 00:07:06,650 --> 00:07:11,220 Because the one on the right was true and do we need to care about this woman the left over here. 128 00:07:11,480 --> 00:07:13,060 So pretty cool huh. 129 00:07:13,250 --> 00:07:14,740 Also of course. 130 00:07:15,660 --> 00:07:18,320 So access is of course access is denied. 131 00:07:18,320 --> 00:07:18,600 OK. 132 00:07:18,620 --> 00:07:21,270 Because we haven't passed a retina scan yet. 133 00:07:21,340 --> 00:07:21,550 OK. 134 00:07:21,560 --> 00:07:28,460 So else or if you know the door code any pest redness redness scan or if I'm Tom Cruise from Mission 135 00:07:28,460 --> 00:07:32,950 Impossible or in else print 136 00:07:35,810 --> 00:07:39,900 Access Denied again. 137 00:07:40,280 --> 00:07:42,560 So print Access Denied again. 138 00:07:42,560 --> 00:07:42,770 All right. 139 00:07:42,770 --> 00:07:48,520 So what we've done here is before we just did NOT operator here we're doing an operator I mean these 140 00:07:48,530 --> 00:07:49,430 both have to be true. 141 00:07:49,430 --> 00:07:51,770 We also used an OR operator. 142 00:07:51,770 --> 00:07:55,400 So ORP your mission and Tom Cruise's Mission Impossible you're going to climb through and you're going 143 00:07:55,400 --> 00:07:56,890 to fall down through the roof. 144 00:07:56,880 --> 00:07:58,160 And you know you don't need the retina. 145 00:07:58,160 --> 00:08:00,230 You don't need a friggin retinas. 146 00:08:00,830 --> 00:08:01,040 All right. 147 00:08:01,040 --> 00:08:02,860 So cool stuff right. 148 00:08:03,220 --> 00:08:06,120 And let's do one more example of the OR operator here. 149 00:08:06,440 --> 00:08:09,130 When you say LET has a door key. 150 00:08:09,140 --> 00:08:12,820 It was false. 151 00:08:15,060 --> 00:08:19,760 So has Dorcy was false let knows over. 152 00:08:19,770 --> 00:08:22,010 Password equals true. 153 00:08:22,240 --> 00:08:30,660 OK then what we can do this is kind of like the Tom Cruise example right if has Dorcy or if knows override 154 00:08:30,660 --> 00:08:33,390 password and Prince. 155 00:08:33,560 --> 00:08:41,610 Welcome to the same thing or one or the other the right one is going to be processed first this nose 156 00:08:41,610 --> 00:08:45,330 over the password and that this is true and it doesn't mean to do anything with the left hand side if 157 00:08:45,330 --> 00:08:48,010 it is false then it's going to move to the left hand side over there. 158 00:08:48,150 --> 00:08:49,440 OK else 159 00:08:53,240 --> 00:09:03,030 you still ain't getting in you for whatever. 160 00:09:03,220 --> 00:09:03,690 Right. 161 00:09:03,860 --> 00:09:05,450 So and or. 162 00:09:05,470 --> 00:09:05,880 OK. 163 00:09:06,010 --> 00:09:07,290 Pretty cool right. 164 00:09:08,380 --> 00:09:12,460 So with these logical operators you can use parentheses there. 165 00:09:12,490 --> 00:09:13,370 You don't need to. 166 00:09:13,450 --> 00:09:16,110 OK they're optional but sometimes they help with readability. 167 00:09:16,140 --> 00:09:17,550 OK like this right here. 168 00:09:17,620 --> 00:09:18,300 This helps me a lot. 169 00:09:18,430 --> 00:09:20,440 Let me know that this is going to kind of run together. 170 00:09:20,680 --> 00:09:21,770 And this is over here. 171 00:09:21,850 --> 00:09:22,910 Sometimes people like to do that. 172 00:09:22,930 --> 00:09:27,120 You don't need to of course but they do work on that just fine. 173 00:09:27,640 --> 00:09:34,090 And we did used to and and as well as that or over here you can use logical operators in the same line. 174 00:09:34,090 --> 00:09:37,900 Really cool stuff you're going to use these a lot when you're making conditional you know conditional 175 00:09:37,900 --> 00:09:38,570 logic. 176 00:09:38,590 --> 00:09:42,400 That's how all programs are run you know and this is a perfect example right here. 177 00:09:42,550 --> 00:09:48,170 If you were actually building an app to well let's say you know even some phone apps or phones like 178 00:09:48,190 --> 00:09:51,700 they now have retinal scanning and stuff like to unlock the phone or even on the iPhone you can use 179 00:09:51,700 --> 00:09:58,330 your thumb you know so if the thumb print worked or you know if it detected your face you know then 180 00:09:58,330 --> 00:10:03,190 you're in you know lots of different options here and these are real real world examples that we're 181 00:10:03,190 --> 00:10:08,920 using here so logical operators are going to use them every single day it's going to take practice doing 182 00:10:08,920 --> 00:10:09,900 this here in the playground. 183 00:10:09,910 --> 00:10:13,100 It's OK but when you are actually building apps you it's really going to start to sink in. 184 00:10:13,120 --> 00:10:18,580 So really good stuff plowing along here in foundationless with hope you're learning a lot. 185 00:10:18,580 --> 00:10:20,030 Marc price at the Afro's.