1 00:00:01,040 --> 00:00:02,440 What's up my peeps. 2 00:00:02,460 --> 00:00:06,870 Mark Bryce you're at DEF slopes dot com in case you've forgotten. 3 00:00:06,970 --> 00:00:11,260 And here there's so my courses you're going to hear that a lot. 4 00:00:11,470 --> 00:00:12,000 That's OK. 5 00:00:12,000 --> 00:00:14,110 You're going to learn to love it. 6 00:00:14,310 --> 00:00:17,670 I've had some people who are like oh this rock and roll music it's driving me crazy. 7 00:00:17,670 --> 00:00:19,360 You do it over and over and over again. 8 00:00:19,530 --> 00:00:22,520 But then everyone else is like this is so cool. 9 00:00:22,590 --> 00:00:26,400 Gets me motivated gets me excited gets the energy going because most of you guys are like doing this 10 00:00:26,400 --> 00:00:27,660 after work at night time. 11 00:00:27,660 --> 00:00:29,330 I'm doing it here near midnight. 12 00:00:29,340 --> 00:00:32,550 You've got to have something to wake you up and excite you about coding. 13 00:00:32,550 --> 00:00:35,800 If you find coding boring it doesn't have to be. 14 00:00:36,120 --> 00:00:36,720 OK. 15 00:00:37,020 --> 00:00:41,110 So that's my inspiration for the hour of course of course. 16 00:00:41,220 --> 00:00:42,510 This lesson is not going to be that long. 17 00:00:42,510 --> 00:00:45,050 I hope we are going to go ahead and get started with the playground. 18 00:00:45,060 --> 00:00:51,630 And today we're going to finish our discussion on making conditional decisions and we're going to talk 19 00:00:51,630 --> 00:00:53,450 about logical operators today. 20 00:00:53,490 --> 00:00:57,420 We've talked about booleans wrote it we've talked about if statements and statements. 21 00:00:57,840 --> 00:00:59,790 Those are called conditionals. 22 00:00:59,790 --> 00:01:05,120 Now we're going to talk about logical operators so logical operators All right. 23 00:01:05,220 --> 00:01:09,210 Next time you go out on a date this is this is what I want you to do. 24 00:01:09,240 --> 00:01:13,340 Be like hey you want to see my logical operators. 25 00:01:13,410 --> 00:01:18,380 Your day is going to be like this guy's awesome and this girl's cool. 26 00:01:19,000 --> 00:01:20,640 Serious do it all the time. 27 00:01:20,640 --> 00:01:21,440 All right. 28 00:01:23,290 --> 00:01:24,910 Don't do that. 29 00:01:24,910 --> 00:01:25,150 All right. 30 00:01:25,150 --> 00:01:25,680 Here we go. 31 00:01:25,690 --> 00:01:31,670 So I'm going to go here into our bulls and comparisons. 32 00:01:31,890 --> 00:01:34,110 Well call us logical operators. 33 00:01:34,140 --> 00:01:37,560 A new folder. 34 00:01:37,600 --> 00:01:38,510 Here we go. 35 00:01:39,040 --> 00:01:39,330 OK. 36 00:01:39,340 --> 00:01:42,410 So again we've talked about true and false and everything else. 37 00:01:42,430 --> 00:01:49,090 Let's talk about how to make decisions and more decisions how to make more better decisions and one 38 00:01:49,090 --> 00:01:52,920 more I wanted to reemphasize on was that your unary operator. 39 00:01:53,230 --> 00:01:55,540 It's also a logical NOT operator. 40 00:01:55,560 --> 00:02:01,320 If that makes any sense so logical NOT operator necessarily sexually the way you say it. 41 00:02:01,630 --> 00:02:09,840 It's also a urinary urinary prefix operator. 42 00:02:09,850 --> 00:02:12,850 Again those are just some terms for you there. 43 00:02:13,000 --> 00:02:14,290 So what is that. 44 00:02:14,290 --> 00:02:20,700 Well let let's say allowed entry equals false. 45 00:02:21,370 --> 00:02:24,530 And there you go. 46 00:02:24,550 --> 00:02:26,210 It's like giving us an air. 47 00:02:26,380 --> 00:02:33,670 And so let what is let let is a constant It means it cannot be changed so I cannot say allowed entry 48 00:02:33,730 --> 00:02:34,530 equals true. 49 00:02:34,660 --> 00:02:39,020 OK so you've got variables and you've got constants 1 you can change one you can't change it's all you 50 00:02:39,020 --> 00:02:39,850 got to know about it. 51 00:02:39,890 --> 00:02:40,890 Pretty simple. 52 00:02:40,990 --> 00:02:41,730 OK. 53 00:02:42,220 --> 00:02:45,460 So loud and true equals false. 54 00:02:45,530 --> 00:02:47,440 You can't get it right you can't get in the building. 55 00:02:47,470 --> 00:02:55,320 So if not allowed entry print access denied. 56 00:02:55,330 --> 00:02:59,360 All right so logical operator. 57 00:02:59,530 --> 00:03:05,900 What it's really saying is it's the opposite of this more or less so if allowed entry is true. 58 00:03:05,920 --> 00:03:10,810 Well we're not asked we're not doing that check we're saying if allowed entry is not true. 59 00:03:10,810 --> 00:03:15,550 So this would be the exact same thing as writing if allowed entry is not equal to true. 60 00:03:15,730 --> 00:03:19,000 That's the exact same thing except this is a little more writing right. 61 00:03:19,000 --> 00:03:24,370 One two three four five six different characters that you have to write are actually five more characters 62 00:03:24,370 --> 00:03:28,350 than you'd need to write on there plus the space anyway and it's long. 63 00:03:28,420 --> 00:03:32,500 So when you become a more veteran programmer you're going to start using this a lot more. 64 00:03:32,500 --> 00:03:37,690 Sometimes it makes sense to say this when you're new because it's easier to read ok and go ahead and 65 00:03:37,690 --> 00:03:37,930 do it. 66 00:03:37,930 --> 00:03:40,270 From now on you can feel free to do this. 67 00:03:40,300 --> 00:03:48,300 It's not equal to true but that the operator is a quick shorthand way to say not ok. 68 00:03:48,430 --> 00:03:50,030 If this is not true. 69 00:03:50,220 --> 00:03:52,570 OK so that makes sense. 70 00:03:52,580 --> 00:03:53,030 OK. 71 00:03:53,200 --> 00:03:56,180 Just emphasizing that you're going to see a lot in other people's code. 72 00:03:57,200 --> 00:03:58,300 A step further. 73 00:03:58,310 --> 00:03:59,020 OK. 74 00:03:59,450 --> 00:04:04,170 Let again Constance you always want to use constants whenever you're not going to change the value if 75 00:04:04,170 --> 00:04:08,230 you are going to change the value is a variable but if you know you're not going to change the value. 76 00:04:08,430 --> 00:04:10,490 Use a constant memory optimize. 77 00:04:10,540 --> 00:04:16,230 Ok so very important news constants at all possible entered door code. 78 00:04:16,270 --> 00:04:17,380 Oh OK. 79 00:04:17,400 --> 00:04:18,290 Now we're entering a door. 80 00:04:18,290 --> 00:04:20,260 Code equals true. 81 00:04:20,770 --> 00:04:21,420 OK. 82 00:04:21,810 --> 00:04:31,260 And let's say there's also a retina scan like it's like Metal Gear Solid ok past retina scan was false. 83 00:04:31,260 --> 00:04:37,350 You know some high tech stuff you know or that game you'd like go and then back the original very first 84 00:04:37,350 --> 00:04:37,820 one. 85 00:04:37,860 --> 00:04:38,990 Is this the cause of the mall. 86 00:04:38,990 --> 00:04:43,740 I think you go knock on the crate and that really dumb A I would come running around and then after 87 00:04:43,740 --> 00:04:46,880 they felt like the noise was no longer threatening they would just chill 88 00:04:49,770 --> 00:04:50,680 irrelevant. 89 00:04:50,980 --> 00:04:51,590 OK. 90 00:04:51,700 --> 00:04:55,370 When it's midnight when you're making videos at midnight you can say whatever you want. 91 00:04:55,450 --> 00:04:58,210 And when you got all these people watching you. 92 00:04:58,880 --> 00:05:00,940 It's how it's going to be. 93 00:05:01,220 --> 00:05:03,190 Try and stop me. 94 00:05:03,190 --> 00:05:04,340 Camera. 95 00:05:04,500 --> 00:05:05,430 He doesn't see me here. 96 00:05:05,440 --> 00:05:12,970 Maybe if you were here what we're going to do is some We're going to use logical operators to make some 97 00:05:12,970 --> 00:05:19,030 decisions so let's say we want the user where the person is coming in to enter the door code and pass 98 00:05:19,030 --> 00:05:20,790 the retina scan. 99 00:05:20,920 --> 00:05:29,380 So what we're going to do is we're going to say if entered door code and past retina scan. 100 00:05:29,790 --> 00:05:34,880 OK we're going to print welcome however. 101 00:05:35,180 --> 00:05:35,930 However 102 00:05:39,730 --> 00:05:45,040 remember the movie Mission Impossible like they're reviewing You know the CIA bunker and how to get 103 00:05:45,040 --> 00:05:47,050 in the guy has to go through all the steps of the retinal scan. 104 00:05:47,050 --> 00:05:48,690 They knew that they couldn't do it. 105 00:05:49,030 --> 00:05:56,520 So this is the way you do it you enter door code and you do a retinal scan but so I say let. 106 00:05:56,530 --> 00:06:03,200 I am Tom Cruise from Mission Impossible. 107 00:06:03,190 --> 00:06:13,750 So if entered door code and past retina scan or if I am Tom Cruise for Mission Impossible then we can 108 00:06:13,750 --> 00:06:15,640 get in print welcome and sure enough. 109 00:06:15,640 --> 00:06:20,600 Mission Impossible Tom Cruise is in the door but of course I am not Tom Cruise. 110 00:06:20,780 --> 00:06:24,070 So this is what does this here. 111 00:06:24,070 --> 00:06:30,730 This is the logical or OPERATOR OK so what's going to happen is the right side is going to be calculated 112 00:06:30,730 --> 00:06:31,420 first here. 113 00:06:31,570 --> 00:06:33,320 OK. 114 00:06:33,460 --> 00:06:34,240 All right. 115 00:06:34,240 --> 00:06:36,490 And so if this is true OK. 116 00:06:36,610 --> 00:06:39,990 It's going to see this or operator and then it doesn't even care about this guy. 117 00:06:40,240 --> 00:06:43,710 If this is true because or means one or the other has to be true. 118 00:06:43,780 --> 00:06:45,280 So this side's going to get run. 119 00:06:45,460 --> 00:06:49,510 And if that's true great otherwise or let's run this and then we do. 120 00:06:49,690 --> 00:06:52,300 If this is true and if this is true. 121 00:06:52,330 --> 00:06:52,650 OK. 122 00:06:52,660 --> 00:06:58,120 So then we so we're at what we're saying here is hey both of these have to be true using the and operator 123 00:06:58,120 --> 00:06:58,300 here. 124 00:06:58,300 --> 00:07:00,260 So this is or this is. 125 00:07:00,310 --> 00:07:01,550 And OK. 126 00:07:01,690 --> 00:07:04,260 This is why it was printing when he was Tom Cruise. 127 00:07:04,270 --> 00:07:06,150 Right. 128 00:07:06,580 --> 00:07:08,620 Because the one on the right was true. 129 00:07:08,620 --> 00:07:11,420 And we didn't really care about this woman the left over here. 130 00:07:11,440 --> 00:07:13,030 So pretty cool huh. 131 00:07:13,210 --> 00:07:14,710 Also of course. 132 00:07:15,660 --> 00:07:20,710 So access is of course access is denied because we haven't passed the retina scan yet. 133 00:07:21,300 --> 00:07:21,500 OK. 134 00:07:21,520 --> 00:07:28,390 So else or if you don't know the door code and you pass ran a scan or if I'm Tom Cruise for Mission 135 00:07:28,390 --> 00:07:32,890 Impossible or in else print 136 00:07:35,770 --> 00:07:39,780 access denied again. 137 00:07:40,210 --> 00:07:42,480 So access denied again. 138 00:07:42,490 --> 00:07:48,010 All right so what we've done here is before we just did NOT operator here we're doing it and operate 139 00:07:48,030 --> 00:07:49,380 I mean these both have to be true. 140 00:07:49,380 --> 00:07:51,740 We also used an OR operator. 141 00:07:51,730 --> 00:07:53,570 So ORP your mission and Tom Cruise. 142 00:07:53,590 --> 00:07:57,490 Mission Impossible you're going to climb through and you're going to fall down to the roof and you don't 143 00:07:57,490 --> 00:07:58,110 need the retina. 144 00:07:58,120 --> 00:08:00,330 You don't need a friggin rottenness. 145 00:08:00,790 --> 00:08:00,990 All right. 146 00:08:01,000 --> 00:08:03,060 So cool stuff right. 147 00:08:03,190 --> 00:08:10,030 And let's do one more example of the OR operator here and say LET has the door key equals false 148 00:08:15,000 --> 00:08:22,280 so has Dorcy was false let knows over password equals true. 149 00:08:22,870 --> 00:08:30,600 And what we can do this is kind of like the Tom Cruise example right if has Dorcy or if knows override 150 00:08:30,600 --> 00:08:33,500 password and prints. 151 00:08:33,970 --> 00:08:42,220 Well same thing or one or the other the right one is going to be processed first this knows my password 152 00:08:42,270 --> 00:08:46,050 and this is true then it doesn't mean to do anything with the left hand side if it is false and it's 153 00:08:46,050 --> 00:08:47,960 going to move to the left hand side over there. 154 00:08:48,130 --> 00:08:49,380 OK else 155 00:08:53,170 --> 00:09:02,940 you still ain't getting in to for whatever. 156 00:09:03,160 --> 00:09:03,840 Right. 157 00:09:04,060 --> 00:09:05,220 And or. 158 00:09:05,410 --> 00:09:05,950 OK. 159 00:09:05,950 --> 00:09:07,010 Pretty cool right. 160 00:09:08,310 --> 00:09:12,420 So with these logical operators you can use parentheses there. 161 00:09:12,430 --> 00:09:16,170 You don't need to get optional but sometimes they help with readability. 162 00:09:16,170 --> 00:09:17,480 OK like this right here. 163 00:09:17,560 --> 00:09:20,450 This helps me get the let me know that this is going to kind of run together. 164 00:09:20,620 --> 00:09:21,700 And this is over here. 165 00:09:21,790 --> 00:09:22,860 Sometimes people like to do that. 166 00:09:22,870 --> 00:09:27,430 You don't need to of course but they do work on that just fine. 167 00:09:27,580 --> 00:09:34,000 And we did used to and and as well as that or over here you can use logic operators in the same line. 168 00:09:34,030 --> 00:09:37,840 Really cool stuff you're going to use these a lot when you're making conditional you know conditional 169 00:09:37,840 --> 00:09:38,530 logic. 170 00:09:38,530 --> 00:09:40,000 That's how all programs are run. 171 00:09:40,030 --> 00:09:42,520 You know and this is a perfect example right here. 172 00:09:42,520 --> 00:09:48,130 If you were actually building an app to well let's say you know even some phone apps or phones like 173 00:09:48,130 --> 00:09:51,640 they now have retinal scanning and stuff like to unlock the phone or even on the iPhone you can use 174 00:09:51,640 --> 00:09:52,240 your thumb you know. 175 00:09:52,240 --> 00:10:00,220 So if the thumb print worked or you know if it detected your face you know then you're in you know lots 176 00:10:00,220 --> 00:10:06,420 of different options here and these are real real world examples that we're using here so logical operators 177 00:10:06,430 --> 00:10:09,840 are going to use them every single day it's going to take practice doing this here in the playground. 178 00:10:09,850 --> 00:10:13,010 It's OK but when you are actually building apps it's really going to start to sink in. 179 00:10:13,060 --> 00:10:17,390 So really good stuff plowing along here in foundationless. 180 00:10:17,650 --> 00:10:18,520 Hope you're learning a lot. 181 00:10:18,520 --> 00:10:19,900 Marc price upstrokes.