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alrighty guys, welcome back to your 7th C++ and in this tutorial
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as promised I'm coming be going over basic c plus plus
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arithmetic. Now, I don't know. I think it was like two tutorials ago.
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I give you guys a variable showed you guys that instead which is setting equal
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to a plain old
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value like this, you can use basic arithmetic like four
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plus 6, and then when you go ahead and print it out,
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X or anything like that, it actually calculated the value
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in printed it out the answer. So, go ahead and run this
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and you see the X now equals four plus six.
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So, aside from addition I want to show you guys
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all the arithmetic operators that you can use and they're a little bit different
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than you might expect. So, let's are the easy ones first.
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The first one is subtraction. And of course like eight minus four.
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This would be valid. If you go ahead and build this, we saw that
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the answer would be four. So, addition, subtraction easy enough.
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But, also aside from addition and subtraction, you can use multiplication,
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but make sure not to use x like that, because that'll mess up.
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In order to multiply in computer programming use the asterisk.
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That's the symbol above 8 (*) on your keyboard and what this is going to do is multiply
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these two numbers,
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eight times four, so now if you go ahead and run this we should get 32.
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And check it out. 32 just like that. So,
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the... well let's go ahead and before I go over this
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let's go ahead and go over...uhm... division.
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In order to use division in computer programming let's go ahead and take
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81 divided by 3. Division,
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the symbol for this is the forward slash.
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So, let's go ahead and take a 81 divide by three and we get
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27 just like that. Simple enough. But check this out. What if we have something
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like
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81 divided by two. Well, this I mean,
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should be forty, but has a remainder 1. So, let's go ahead and try to build and run
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this
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and see we get. Well, it just says forty, that's
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not entirely right, because it should have a remainder of one. So,
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let's go ahead and to build and run this and see what we get. We're working with integers
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and we don't know any other data type, so how can we get that remainder?
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well whenever we want to use the remainder
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we need to use something called the modulus operator. That is 
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the percent sign like this. What this is going to do
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is is gonna give you the remainder at the answer it's not gonna say for the
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remainder 1
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it's just gonna give you that one so let's go ahead and build
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in run this. And you can see that whenever we do
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81 modulus two, its gonna give us the remainder
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which is one. So, let me show you guys a better example are maybe
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24 module seven. Well we know that
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21, excuse me, 24 divided by seven is
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3 with .... the remainder 3.
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So, let's go ahead build and run this. And again it doesn't say
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3 remainder 3. It just says the remainder which is three.
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Simple enough. So now that we know all the arithmetic operators,
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I can begin teaching you guys about order of precedence.
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Now aside from just you know one number
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arithmetic operator, another number, you can have
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complex calculations like six times four plus
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8 times 4 plus
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9 divided by 20. And if we go ahead and build and run this
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we see what we get: 56. You're saying alright.
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So, what order is this doing this in? Is it doing
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six times for and then plus 8, or is it doing you now
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four plus 8 and times that by six, because
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depending on how you do it its is gonna come out with a different result so
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the basics is this if you remember way back in like 7th grade math
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you know something called your associative property and that's pretty
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much it
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anything that's in parentheses gets done first
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if you don't have any print sees because like this
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it does of a multiplication in Division
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which should be this this and this
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it's going to do that first and then is going to your decision
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addition and subtraction
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if you don't have if you know if you just have liked for
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plus a plus 7 on their centauri
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than is again into a possum fur store for plus a first
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it really doesn't matter comes at the same either way the only time you have
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arm varying answers is when you have like
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for plus 3
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times seven for example if you did for place 3
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lb7 time seven would be 49
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but when I every run this
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will easy box we at 25 why's that because he uses the associative property
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actually multiplies for switches sometimes three and that's 21
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plus for which is 25 so again
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if you want to explicitly say four poster the first
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you need to surround the in parentheses so now when everybody run this
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its gonna run your practice his first and say re: four-plus
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3 because seven time seven because forty-nine sir member
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the rule is this parentheses first than your multiplication and division
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and then your addition and subtraction so
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remember their and if you get computers is called the associative property
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should have learned in like eighth-grade matter night cream at I'm be some great
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I don't know I can remember as a long time ago for now and that's all i wanna
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talk to you guys about
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basic arithmetic and how it works in C pas plus
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so for now that's all you guys get something your ass Russian store
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there any questions go to my our website the new boss in a comment click on Form
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and you can ask me there so one last time inc.'s Russian company subscribe
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now see you next video