1 00:00:01,140 --> 00:00:06,570 So you look at the different arithmetic operators there are not a few rolls that may come into play 2 00:00:06,750 --> 00:00:09,450 when using arithmetic operations. 3 00:00:09,450 --> 00:00:11,550 Knowing these rules is very important. 4 00:00:11,670 --> 00:00:14,700 And let's look at what these rules are. 5 00:00:15,330 --> 00:00:21,240 We can have instances where we come across expressions such as this which have more than one otic Medek 6 00:00:21,240 --> 00:00:22,240 operation. 7 00:00:22,680 --> 00:00:24,310 So it's a compound expression. 8 00:00:24,540 --> 00:00:29,250 But the question is in what order are the subexpressions evaluated. 9 00:00:29,400 --> 00:00:36,090 That is what the first ad 5:01 line or would do for us multiply 2 and 5 and then add the result to 3 10 00:00:37,230 --> 00:00:42,900 dollar has a couple of set rules called operator precedence rules for this kind of compound expression 11 00:00:42,900 --> 00:00:45,220 . 12 00:00:45,240 --> 00:00:51,810 First rule is that multiplicative operators have higher precedence over any two operators multiplicative 13 00:00:51,810 --> 00:00:57,030 Operators Group multiplication division and Margulis whereas any two operators include addition and 14 00:00:57,030 --> 00:01:02,140 subtraction with just one example expression but looks something like this. 15 00:01:02,730 --> 00:01:10,020 That is to an Freiler multiplied first as multiplication has higher presidents once the first rule is 16 00:01:10,020 --> 00:01:10,640 applied. 17 00:01:10,740 --> 00:01:17,250 Then the second rule is that operators within the same group will be evaluated from left to right and 18 00:01:17,250 --> 00:01:21,600 by applying this rule on our example expression we would have something like this. 19 00:01:21,750 --> 00:01:27,330 That is all left to what operators belong to the same group which is additive two operators group and 20 00:01:27,330 --> 00:01:29,650 so they are evaluated from left to right. 21 00:01:30,240 --> 00:01:37,260 So 9 or are that first then three is subtracted from the desert and a new reserve is finally added to 22 00:01:37,400 --> 00:01:40,610 do in to fight. 23 00:01:40,680 --> 00:01:45,590 Finally note that you can use pattern sources to change the order of evaluation. 24 00:01:45,660 --> 00:01:50,290 So in our example we can force the expression to be evaluated this way. 25 00:01:50,550 --> 00:01:57,060 He had 3 and 2 and 5 or 9 will be added separately but the sum of three and two will be multiplied with 26 00:01:57,060 --> 00:02:03,760 5 due to rule 1 and the result will be proctored from five plus nine. 27 00:02:03,900 --> 00:02:06,160 Next is open and promotion rule. 28 00:02:06,450 --> 00:02:09,170 That is it has something to do with promoting an operator. 29 00:02:09,390 --> 00:02:11,540 Let's see what it is. 30 00:02:12,120 --> 00:02:20,280 It states that operate in smaller than and that is byte shot or car are promoted to and hit Here's an 31 00:02:20,280 --> 00:02:21,390 example. 32 00:02:21,600 --> 00:02:25,260 Here is the Ajume that the two operands of by date type. 33 00:02:25,410 --> 00:02:30,460 Then they will be first promoted to end before any operation is applied. 34 00:02:31,470 --> 00:02:32,910 And here is another example. 35 00:02:32,910 --> 00:02:33,700 The carburetor. 36 00:02:33,740 --> 00:02:42,390 I recall that card Streater I said 16 bit unsigned integer whose range is zero to the power of 16 minus 37 00:02:42,390 --> 00:02:43,150 one. 38 00:02:43,670 --> 00:02:48,310 So if God is used an IT operation it will also be promoted to an end. 39 00:02:48,780 --> 00:02:49,750 So in this example. 40 00:02:49,770 --> 00:02:53,940 Characters IA and B are promoted to the respective decimal values. 41 00:02:54,000 --> 00:02:57,690 97 98 and you of 16. 42 00:02:57,690 --> 00:02:59,800 So the final result will be 195. 43 00:03:00,450 --> 00:03:06,330 Shortly we will also be a quick demo where we will see examples of current use getting promoted to and 44 00:03:09,300 --> 00:03:15,450 next let's look at another rule which we can refer to as same type operations rule and this rule states 45 00:03:15,450 --> 00:03:23,190 that if both our parents are in long float our bubble then the arithmetic operation is carried out in 46 00:03:23,190 --> 00:03:28,060 that type and also evaluated the value of that same day. 47 00:03:28,950 --> 00:03:34,220 Here are a couple of examples where the operands are integers in the second example. 48 00:03:34,290 --> 00:03:40,260 Even though the characters are at this point fine the value return will be zero as spawn 5 is not an 49 00:03:40,260 --> 00:03:41,200 integer. 50 00:03:41,310 --> 00:03:43,900 So point five was truncated to zero. 51 00:03:45,120 --> 00:03:51,150 Previous rule was called same type operations stored on the operations but of SAME TIME NEXT rule is 52 00:03:51,150 --> 00:03:56,310 about operands being of different types and so is referred to as mixed type operations. 53 00:03:56,310 --> 00:03:58,640 Let's see what it states. 54 00:03:59,130 --> 00:04:05,400 It states that if both operands belong to different types then the value of the smaller type is automatically 55 00:04:05,400 --> 00:04:08,780 promoted to larger type. 56 00:04:09,000 --> 00:04:11,270 And here is the order of promotion. 57 00:04:11,270 --> 00:04:17,540 Note that if you have long and flautas operands longest promoted to float even though long 64 bit untrue 58 00:04:17,550 --> 00:04:19,750 disturbed little bit. 59 00:04:20,600 --> 00:04:26,700 Here is a similar example as in the previous light did BORTOLI draws 1 and 2 are integers and so the 60 00:04:26,700 --> 00:04:29,730 result was also an integer which was 0. 61 00:04:30,120 --> 00:04:36,670 Here in both examples one of the operands is a double and so due to this particular rule the interior 62 00:04:36,670 --> 00:04:43,970 operand is promoted to double and so the final result is a double value point five. 63 00:04:44,010 --> 00:04:50,830 Here is how an expression involving a car and float are evaluated got is first promoted to and the operand 64 00:04:50,850 --> 00:04:52,160 promotion rule. 65 00:04:52,290 --> 00:04:55,000 Then it is promotor to float DUPERE this rule. 66 00:04:55,200 --> 00:04:59,520 And finally both the floats will be added on. 67 00:04:59,550 --> 00:05:02,660 Here is a very nice example in this expression. 68 00:05:02,700 --> 00:05:09,570 First division operation is applied as both operators are from the same group that is belong to multiplicative 69 00:05:09,630 --> 00:05:13,500 Operators Group and hence are evaluated from left to right. 70 00:05:13,680 --> 00:05:17,180 So that's the operator president's rule in action. 71 00:05:17,190 --> 00:05:23,130 Next since 9 and 5 are in the first same type operations rule is applied and the result of division 72 00:05:23,220 --> 00:05:25,980 will be an integer value 1. 73 00:05:25,980 --> 00:05:32,460 No we are left with integer under double N since integers are smaller they are tight due to mixed type 74 00:05:32,460 --> 00:05:33,230 operations. 75 00:05:33,240 --> 00:05:38,680 When it gets promoted to double and the final result will be double. 76 00:05:38,720 --> 00:05:45,930 In general the largest data type in an expression determines the type of the final result. 77 00:05:45,930 --> 00:05:51,340 Now as mentioned earlier let's do a quick them off Oper in promotion rule a new method called Cartaya 78 00:05:51,350 --> 00:05:56,970 promotion has been added to basics demo class which can be downloaded from the resources section. 79 00:05:56,970 --> 00:05:59,360 Let's look at the program now. 80 00:06:00,660 --> 00:06:06,360 OK here is the numerator cark by promotion and it's invoked from the main method and there are a bunch 81 00:06:06,360 --> 00:06:07,960 of print statements here. 82 00:06:08,220 --> 00:06:13,350 So let's just go ahead and run this program and we will look at the Outlook and then we will discuss 83 00:06:13,350 --> 00:06:14,470 the print statements. 84 00:06:14,480 --> 00:06:19,430 Ok ok so I'm already in the basics directory so let me just run it. 85 00:06:19,440 --> 00:06:20,920 It's already compiled. 86 00:06:21,420 --> 00:06:22,820 So here is the output. 87 00:06:23,030 --> 00:06:27,990 Let's just look at that last statement because it was already covered in the in the slight. 88 00:06:28,300 --> 00:06:35,990 So it's just printing it just adding two characters a and b and the output is 195. 89 00:06:36,340 --> 00:06:39,150 And that's because off the operand promotional. 90 00:06:39,210 --> 00:06:44,400 So that's because here we have two characters on both the characters as we discussed will be promoted 91 00:06:44,400 --> 00:06:53,220 to integers so the corresponding integer values and UAD of 16 is 97 98 and so you'll see the final value 92 00:06:53,220 --> 00:06:55,110 as the same as 1 95. 93 00:06:55,260 --> 00:07:00,920 OK so that's what is happening even even though you're adding two characters here. 94 00:07:00,990 --> 00:07:08,030 Now the first one is very simple it's simply printing the carbon carbon is basically is assigned a decimal 95 00:07:08,050 --> 00:07:13,590 50 so decimal 50 is equal to you'd be up in uk of 16 its value. 96 00:07:13,890 --> 00:07:15,850 So if you see here it's printing do. 97 00:07:15,900 --> 00:07:18,330 We already know that from our characters demo. 98 00:07:18,780 --> 00:07:20,310 So it's just printing too. 99 00:07:20,490 --> 00:07:26,000 So carbon is basically to write on the second print statement here. 100 00:07:26,130 --> 00:07:33,240 It's subtracting carbon from 73 so it's 73 minus carbon carbon is basically two. 101 00:07:33,600 --> 00:07:40,100 So it gets promoted to án And so the equal in decimal value is once again 50 so it's going back to 50 102 00:07:40,160 --> 00:07:40,450 . 103 00:07:40,680 --> 00:07:42,790 So it would be 73 minus 50. 104 00:07:43,010 --> 00:07:48,630 And so we are seeing 23 as the final 73 minus 50. 105 00:07:48,720 --> 00:07:55,230 So in the next print statement we are doing we are subtracting character 3 from carbon. 106 00:07:55,320 --> 00:07:58,570 So carbon has two and this is three. 107 00:07:58,720 --> 00:07:59,540 So. 108 00:07:59,560 --> 00:08:05,270 So both of them are characters essentially and both of them get promoted to two. 109 00:08:05,290 --> 00:08:10,420 And so carbon will get promoted to end and the value will be 50. 110 00:08:10,470 --> 00:08:13,930 And since this is three it will get promoted to 51. 111 00:08:14,250 --> 00:08:16,640 So 51 us 51 us minus 1. 112 00:08:16,730 --> 00:08:18,320 And that's what we see here. 113 00:08:18,690 --> 00:08:19,620 OK. 114 00:08:19,620 --> 00:08:21,830 So that's the operant promotion run. 115 00:08:22,080 --> 00:08:25,490 And so basically we look at that four kinds of rules. 116 00:08:25,500 --> 00:08:32,400 One is to operate or presidents run then operate in promotion rule then same type operations rule and 117 00:08:32,790 --> 00:08:34,350 Mixter type operations. 118 00:08:34,460 --> 00:08:35,040 OK. 119 00:08:35,070 --> 00:08:36,360 So these are very important. 120 00:08:36,360 --> 00:08:43,980 So please do understand them very well and you can also expect some questions in the quest for him from 121 00:08:43,980 --> 00:08:45,060 this particular lesson. 122 00:08:45,060 --> 00:08:45,490 OK. 123 00:08:45,540 --> 00:08:51,210 And you can also download this program and play around really familiarize yourself with with the with 124 00:08:51,210 --> 00:08:52,050 this lesson. 125 00:08:52,350 --> 00:08:52,650 OK. 126 00:08:52,660 --> 00:08:53,360 And thank you. 127 00:08:53,380 --> 00:08:54,750 And happy coding.