1 00:00:00,150 --> 00:00:04,440 Now I'm on a hunch about the X or are logical OPERATOR OK. 2 00:00:04,440 --> 00:00:06,890 So X or. 3 00:00:07,070 --> 00:00:07,500 OK. 4 00:00:07,530 --> 00:00:14,520 So as you can see here in order to actually use the x or logical operator in your code you actually 5 00:00:14,520 --> 00:00:18,600 need to press the shift plus the number 6 on your keyboard. 6 00:00:18,600 --> 00:00:25,950 And design is the sign for X or are logical operator when you want to actually use this logical operator 7 00:00:25,950 --> 00:00:26,710 in your code. 8 00:00:26,810 --> 00:00:27,030 OK. 9 00:00:27,030 --> 00:00:30,740 Now let me actually explain what this actually logical operator does. 10 00:00:30,740 --> 00:00:34,010 The x or convention has one logical operator. 11 00:00:34,020 --> 00:00:35,810 This is the logical operator OK. 12 00:00:36,000 --> 00:00:44,280 And this results in a true value only if the boolean expressions it combines have opposite values. 13 00:00:44,380 --> 00:00:52,020 Ok if both are true or both are false they X or are logical operator produces a false value. 14 00:00:52,020 --> 00:00:57,340 OK so now let me actually show you some real examples to make this concept more clear for you. 15 00:00:57,360 --> 00:00:58,070 OK. 16 00:00:58,560 --> 00:01:05,760 So for example I want to create another variable here and that is the type of my variable is it and 17 00:01:05,820 --> 00:01:08,580 the name of my variable is for example number 1. 18 00:01:08,670 --> 00:01:09,350 OK. 19 00:01:09,600 --> 00:01:11,940 And I want to assign a value to my variable. 20 00:01:11,940 --> 00:01:14,210 For example 59. 21 00:01:14,400 --> 00:01:17,580 And then at the end of my statement I need to put in a semicolon. 22 00:01:17,580 --> 00:01:18,200 OK. 23 00:01:18,540 --> 00:01:26,850 So and here I want to actually create another variable of it a boolean data type so boolean and the 24 00:01:26,850 --> 00:01:32,940 name of my variable would be Chan boy home. 25 00:01:33,400 --> 00:01:33,910 OK. 26 00:01:34,020 --> 00:01:40,070 And then I can assign a value to my variable for example fonts and an idea of my statement. 27 00:01:40,110 --> 00:01:41,960 I need to put in a semi-colon OK. 28 00:01:42,030 --> 00:01:51,120 So now I want to actually output the value of these can by valuable to the council system that out that 29 00:01:51,120 --> 00:01:59,610 print line and then inside the prentices I just need to refer to the name of my variable can by home. 30 00:01:59,860 --> 00:02:00,500 OK. 31 00:02:00,720 --> 00:02:04,110 And then at the end of my statement I ended up with a semi-colon. 32 00:02:04,440 --> 00:02:10,940 So if I run my project now as you can see it's going to output this value to the concert OK. 33 00:02:10,980 --> 00:02:14,350 Disvalue is the value of this trend by home variable. 34 00:02:14,400 --> 00:02:23,450 Ok so now let me actually comment out this line of code here and I want to change the value of my hand 35 00:02:23,500 --> 00:02:24,760 by home variable. 36 00:02:24,870 --> 00:02:30,150 So I just need to revert to the name of my variable can by home. 37 00:02:30,930 --> 00:02:36,230 And then I can actually assign a combination of expressions to my variable. 38 00:02:36,240 --> 00:02:45,470 So the first expression would be Nahm one must be less than or equal to 50. 39 00:02:45,720 --> 00:02:46,190 OK. 40 00:02:46,230 --> 00:02:50,300 And then I use the x or logical operator as you can see here. 41 00:02:50,340 --> 00:02:50,980 OK. 42 00:02:51,300 --> 00:02:55,240 And again I create another expression here. 43 00:02:55,450 --> 00:03:00,000 Now I'm fun must be greater than 40. 44 00:03:00,180 --> 00:03:01,360 OK. 45 00:03:02,100 --> 00:03:05,760 And then at the end of my statement I need to put in a semi-colon OK. 46 00:03:06,150 --> 00:03:12,480 So now if I want to output the value of my variable to the console I just need to type in here and system 47 00:03:12,810 --> 00:03:15,370 that out that princeling. 48 00:03:16,140 --> 00:03:22,560 And then inside the apprentice's I need to refer to the name of my ABOUT can by home. 49 00:03:23,280 --> 00:03:26,610 And then at the end of my statement I need to put in a semi-colon. 50 00:03:26,700 --> 00:03:33,240 So if I run my project as you can see it's going to output this value to the council OK. 51 00:03:33,330 --> 00:03:38,700 So let me ask you to explain once again that what this logical operator does. 52 00:03:38,700 --> 00:03:39,230 OK. 53 00:03:39,300 --> 00:03:48,480 So this logical operator results in a true value only if the boolean expressions it combines have opposite 54 00:03:48,480 --> 00:03:49,140 values. 55 00:03:49,170 --> 00:03:53,310 So as you can see here these expressions are boolean expressions. 56 00:03:53,340 --> 00:03:59,940 OK we call these expressions boolean expressions because these expressions actually return a boolean 57 00:03:59,940 --> 00:04:00,390 value. 58 00:04:00,390 --> 00:04:01,480 True or false. 59 00:04:01,590 --> 00:04:04,480 OK so we call them boolean expressions. 60 00:04:04,560 --> 00:04:11,600 So this logical operator actually results in a true value only if the boolean expression is. 61 00:04:11,640 --> 00:04:14,490 It combines have opposite values. 62 00:04:14,490 --> 00:04:19,160 So as you can see here this expression here evaluates to false. 63 00:04:19,170 --> 00:04:19,920 Why. 64 00:04:19,950 --> 00:04:25,040 Because the value of the noun number one variable is greater than number. 65 00:04:25,080 --> 00:04:29,610 Fretty as you can see here 59 is greater than number 40. 66 00:04:29,680 --> 00:04:36,960 Ok but in this expression I am telling the computer that the value of the now one variable must be less 67 00:04:36,960 --> 00:04:44,230 than or equal to number 30 in order to evaluate this expression to true. 68 00:04:44,700 --> 00:04:51,780 And in this expression I am telling the computer that the value of the number one variable must be greater 69 00:04:51,780 --> 00:04:57,820 than 40 in order to evaluate this expression to true. 70 00:04:58,050 --> 00:05:01,530 So as you can see here this expression evaluates to TRUE Why. 71 00:05:01,630 --> 00:05:06,660 Because the value of the novel non-valid valuable is greater than 40. 72 00:05:06,760 --> 00:05:09,610 The value of the number one variable is fifty nine. 73 00:05:09,630 --> 00:05:12,090 OK so fifty nine is greater than 40. 74 00:05:12,220 --> 00:05:21,270 So this expression evaluates to true logical operator results in a truth value only if the boolean expressions 75 00:05:21,340 --> 00:05:24,050 it combines have opposite values. 76 00:05:24,070 --> 00:05:24,620 OK. 77 00:05:24,790 --> 00:05:28,630 So as you can see here the value of this expression evaluates to false. 78 00:05:28,630 --> 00:05:29,280 OK. 79 00:05:29,380 --> 00:05:32,190 And the value of this expression evaluates to true. 80 00:05:32,230 --> 00:05:35,940 So this logical operator results in a true value. 81 00:05:35,950 --> 00:05:36,470 Why. 82 00:05:36,580 --> 00:05:44,460 Because the boolean expressions that this logical operator combines have opposite values. 83 00:05:44,470 --> 00:05:45,160 OK. 84 00:05:45,250 --> 00:05:52,350 So this expression here evaluates to false and this expression here evaluates to true. 85 00:05:52,480 --> 00:05:56,290 So the entire expression evaluates to TRUE. 86 00:05:56,410 --> 00:05:57,390 Why. 87 00:05:57,400 --> 00:06:00,490 Because I am using this logical operator here. 88 00:06:00,580 --> 00:06:06,790 OK so this expression evaluates to false and this expression evaluates to TRUE. 89 00:06:06,880 --> 00:06:07,330 OK. 90 00:06:07,480 --> 00:06:10,170 So the entire expression evaluates to TRUE. 91 00:06:10,300 --> 00:06:10,880 Why. 92 00:06:10,990 --> 00:06:18,640 Because this operator here results in a true value only if the boolean expression is that it combines 93 00:06:18,850 --> 00:06:20,180 have opposite values. 94 00:06:20,200 --> 00:06:24,430 OK so these boolean expressions have opposite values. 95 00:06:24,430 --> 00:06:25,010 OK. 96 00:06:25,240 --> 00:06:31,170 So as you can see in the console the true value is now actually out with a to the console like so. 97 00:06:31,180 --> 00:06:39,640 Now if I for example change this value to something else for example 59 as you can see now this expression 98 00:06:39,670 --> 00:06:41,060 evaluates to TRUE. 99 00:06:41,140 --> 00:06:41,770 Why. 100 00:06:41,800 --> 00:06:48,330 Because the value of the number one variable is now equal to that to this number here. 101 00:06:48,320 --> 00:06:49,080 OK. 102 00:06:49,660 --> 00:06:54,480 The value of this number one variable is now equal to this number here. 103 00:06:54,480 --> 00:06:55,600 OK 59. 104 00:06:55,870 --> 00:07:01,690 So now if I run my project now it's going to actually be out with the false value to the console as 105 00:07:01,690 --> 00:07:03,310 you can see here. 106 00:07:03,350 --> 00:07:07,270 OK this value is the value of this variable here. 107 00:07:07,330 --> 00:07:07,810 OK. 108 00:07:07,840 --> 00:07:11,300 Why is it actually out with had the false value to the console. 109 00:07:11,440 --> 00:07:20,170 Because this logical operator here results in a true value only if the boolean expressions it combines 110 00:07:20,350 --> 00:07:22,430 have opposite values. 111 00:07:22,500 --> 00:07:30,950 Ok if both are true or both are false this logical operator here produces a false value. 112 00:07:31,060 --> 00:07:31,860 OK. 113 00:07:32,380 --> 00:07:40,190 So as you can see here both of these expressions here actually evaluates to true so. 114 00:07:40,410 --> 00:07:47,660 So the entire expression evaluates to false and that false value is assigned to this variable here. 115 00:07:47,710 --> 00:07:52,440 And as you can see here in the console this false value is now out with to the console. 116 00:07:52,480 --> 00:07:57,860 OK so now let me actually explain to you what's going on here in line 42. 117 00:07:57,970 --> 00:07:59,460 I created a variable. 118 00:07:59,470 --> 00:08:00,140 Now what. 119 00:08:00,230 --> 00:08:07,310 OK the data type of my variable is int and then I assigned a value to my variable number 59. 120 00:08:07,360 --> 00:08:08,080 OK. 121 00:08:08,350 --> 00:08:17,080 And in line 43 I created another variable with the boolean data type and I gave a name to my variable. 122 00:08:17,170 --> 00:08:19,380 For example can buy home OK. 123 00:08:19,390 --> 00:08:22,920 And I assigned a value to my valuable for example fots. 124 00:08:22,960 --> 00:08:23,620 OK. 125 00:08:23,620 --> 00:08:31,070 And in line 47 as you can see here I decided to change the value of my boolean variable. 126 00:08:31,270 --> 00:08:37,510 So I just referred to the name of my variable and then I actually put a combination of expressions here 127 00:08:38,170 --> 00:08:44,190 in order to actually assign the value of the entire expression to my variable. 128 00:08:44,230 --> 00:08:44,970 OK. 129 00:08:45,280 --> 00:08:49,740 So as you can see here the first expression here evaluates to TRUE. 130 00:08:49,860 --> 00:08:54,470 OK now one is less than or equal to the number 59. 131 00:08:54,670 --> 00:08:59,980 So the value of the number one variable is 59 and this number is 59. 132 00:09:00,070 --> 00:09:02,050 So this expression evaluates to TRUE. 133 00:09:02,080 --> 00:09:03,010 OK. 134 00:09:03,520 --> 00:09:06,640 And then I am using the logical operator as you can see. 135 00:09:07,060 --> 00:09:14,980 And then this expression again evaluates to true because the value of this non-valid valuable is greater 136 00:09:14,980 --> 00:09:16,150 than 40. 137 00:09:16,420 --> 00:09:17,000 OK. 138 00:09:17,170 --> 00:09:19,840 As you can see 59 is greater than 40. 139 00:09:19,900 --> 00:09:23,550 So this expression now evaluates to true so. 140 00:09:23,710 --> 00:09:29,840 So this operator results in a true value only if the boolean expression is. 141 00:09:29,890 --> 00:09:32,280 It combines have opposite values. 142 00:09:32,350 --> 00:09:38,890 So for example if I want to actually evaluate the entire expression through this expression here for 143 00:09:38,890 --> 00:09:41,590 example must evaluate to true. 144 00:09:42,250 --> 00:09:45,990 And this expression here must evaluate to false. 145 00:09:46,000 --> 00:09:47,080 OK. 146 00:09:47,250 --> 00:09:51,320 Or this expression here must evaluate to false. 147 00:09:51,580 --> 00:09:54,690 And this expression here must evaluate to true. 148 00:09:54,820 --> 00:10:04,500 OK this logical operator here results in true value only if the boolean expressions these are the boolean 149 00:10:04,500 --> 00:10:11,090 expressions only if the boolean expressions it combines have opposite values. 150 00:10:11,130 --> 00:10:12,780 OK so this is very important.