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So let's take a look at the arithmetic operators and most of these you should be pretty familiar with.

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So there's addition which adds to numbers, subtraction, which subtracts one number from another multiplication.

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Multiply two numbers together.

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Division divides one number into another.

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Here's the first caveat.

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You cannot divide zero and zero because that will give you infinity.

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And that and computers have a problem with infinity.

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Now we get to a couple that maybe you haven't heard of.

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A remainder is the remainder of integer division.

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So is a division of five divided by two is to.

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Because you have an urgers, not 2.5, but the remainder is one.

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And then, exponentiation, there's something raised to a power like 10 to the third is one thousand.

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And then the unary plus, you don't see it as much, but sometimes you do that just as create a positive

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number out of a variable.

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And this is, you know, you need a variable and you don't need a variable.

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I'm sorry, you say plus five.

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So that just says make this a positive number and then the union minus is make this negative number.

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And you see this a little bit more often because you want to be able to say negative five, but you

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can also say negative X.

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So if X had the value of five, would not be negative five.

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If X had the value of negative five, it'd be five.

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And it does actually change the value of X it just as a result, I don't increment in order decrement

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operate on one variable there.

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Unary.

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And what they do is they either add one or they subtract one.

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The prefix double plus sign adds one or subtract one before the variable is used, the post fixed where

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the plus signs or the minus signs are on the right are incremented or decrements after the variables

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used as an example.

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Let's take a look at that next.

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Once again, I made a copy of the starter project, and so we're going to just remove this hello world.

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We don't need it and we'll do a little bit of operating.

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So some of this should be fairly obvious.

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And let's start out by doing some of them with literal values

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and we'll say five plus seven and let's make some copies of this and just do it for the basic arithmetic

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operations.

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Plus minus times divide.

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And is an asterisk and divide is a flash, let's go and run these and see the result.

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So 12 percent is 12 minutes is negative to five times.

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Seven is thirty five and five divided by seven, I'm assuming.

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Is this OK, let's keep going.

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So let's switch them around for the remainder because it makes a little more sense.

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Seven divided by five

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and do the remainder.

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And we'll also do a exponentiation or a power seven to the fifth power, so let's see what happens with

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those.

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So seven divided by five, that's this one point for.

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So that's the decimal version of it, seven remainder five is to.

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So, you see, if you did an integer division, it's just one, so you don't get the point four and

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there's a remainder of two and then seven to the fifth power of sixteen thousand eight hundred and seven.

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OK, these are all fairly straightforward.

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So what are we got next?

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OK, so next we'll do the unary plus in the unary minus.

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So.

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And Unary operates on only one variable.

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So if I say plus eight or minus eight,

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that gives us those values and that should be fairly obvious what's going to return?

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What Satan might have said.

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Now let's do the same thing with variables instead of literals.

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So let's see what's the quickest way I can make this happen, let's say let up or one equals five and

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what appear to equals seven and we'll make a copy of all these council logs

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and let's.

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Come at these up.

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So I'm going to do a replacement on five

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to.

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Offer one.

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And I'm just going to.

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Go past these, and so then I'll start clicking replace.

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Good beginnings, so then seven or two.

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OK.

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So replace those, let's just do this on Opper one

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and say we'll let it run.

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We'll tell you how I requested there to.

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Five, seven.

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A little bit too far, and so now I get the pretty much the same results, except we don't have eight

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and minus eight, but we have five and minus seven.

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So you see at minus the seven.

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All right.

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The only other one we need to look at is the decrements and the increment.

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So the way that works is we have our value.

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Opper one is five and you can't do it on a literal.

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So if I say council that log plus plus opper one and let's run, that's what happens.

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So opera one was five and six.

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What happens?

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What was removed from the confusion

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and let's just run it again, just to make sure we're clear so it's six because it incremented by one,

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but if I move the plus size to the end.

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We run that.

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It's still five, but it's not still five at the end, if I said console that log off or one without

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doing anything the second time, it'll have the value of six.

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So it was five, it was used in output with council dialogue, but it was enterable by one.

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So the next time we did it, Disvalue six.

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Decorating is the same sort of thing.

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So if I say minus minus one, An or one.

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He goes back to five.

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But if I do it.

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Postfix.

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It's took us back to five, but after the council walk.

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All right, one of the thing that I mentioned was order of precedence, so let's take a look at that.

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So I want to say that the fine, if I say

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let result equals offer one plus offered two times OP or two plus five, put a little one there.

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So this is five plus seven is 12 and produce 12.

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So 12 times seven is 80 for.

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Plus five is 89, but that's not what the results are going to be.

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And the reason is because let's just see, first of all, explain the reason.

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It's fifty nine, and the reason is because it does the the multiplication first, so does seven times

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seven is forty nine and then it does the adding.

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So 49 plus five is fifty four, plus five is fifty nine.

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That's the answer we got right.

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Yep.

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Now how can we get the answer that I originally thought we were going to get.

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We can get it by using parentheses to specify the order that things are going to happen by elevating

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the priority.

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So this is add them first and then multiply them.

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And I was totally off on what that came up with before.

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Well, that's because I was going left to right, so that would have been fine.

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Let's let's get the view I wanted before.

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So I didn't I wanted to add these first and then multiply times up or two and then add five.

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So that's at 89, and if I really want to be specific, I could put a parenthesis here and one here

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and that would really be specific.

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I could also do one here.

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And one out here, and that would really tell you that, hey, we have to do our for one plus up or

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two first and then we have to do time's up or two, and then we have to add five.

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So it's going to get the same result.

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So that's an introduction to arithmetic operations.

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Next, we'll look at relational operators.