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We can use math operators to operate on values.

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So far, you learned about five types of values into four whole numbers, long for large numbers, double

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for decimals, car for single characters and string for a string of characters also known as text.

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You can use math operators to play with these values and operate on them.

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And so in the next two videos, we're going to look at all the math operators in Java.

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Namely, the plus operator, which is used to add values, the minus operator to subtract values, the

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multiplication operator represented by the asterisk, the division operator represented by the front

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slash the modulus operator, which returns the remainder of a division, the add one operator, which

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increases their value by one B. Subtract one operator, which decreases a value by one.

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The add by operator, which increases the value by the number on the right, and you subtract by operator,

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which decreases the value by the number on the rights.

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What a list.

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All right.

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For this lesson, we're going to start by looking at the first four operators.

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First thing I'll need you to do is create a new class by yourself inside the section to folder, making

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you file name math operations Java and make sure the class has a main method.

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OK, first, we need to make some variables because math operators like you operate on values, so we'll

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need to set up some variables with store values inside them.

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We'll start by making two into variables and bag of sweets one.

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Is equal to five.

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And int.

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Bag of sweets to.

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Is equal to 10.

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Now we're going to make two long variables.

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Long stars in Milky Way.

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Is equal to and there are 2.5 billion stars, civil right to five and eight zeroes, one, two, three,

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four, five, six, seven, eight.

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And don't forget the L to reassure Jova that, hey, we are going to store this in a long variable and

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that will say long.

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Stars in.

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Andromeda.

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Is equal to and there are a trillion stars, so we'll say one and 12 zeroes, but don't forget the al.

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Finally will make two double variables, double test score is equal to six point seven.

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And double bonus marks.

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Is equal to 2.5 in any case, we created six variables to enter variables.

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Too long variables and two double variables.

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Now we can start using operators and as we play around with these operators, you're going to notice

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a very interesting pattern in operation between home numbers.

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Always returns a whole number and an operation between decimals will always preserve the decimal.

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I want you to keep this in mind as we go through every operator.

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We'll start with the plus operator, you've seen it before, the plus operator adds to values and the

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symbol is without a doubt, the plus side.

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So we're going to add every pair of end long and double values and print each results system.

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Dot out, dot print line.

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Bag of sweets, one plus bag of sweets, two.

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Once again, systemd out front line stars in Milky Way, plus stars in Andromeda.

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Third time system got out front line test score, plus bonus marks.

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We're in a compiler code.

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Now, I ask you, isn't it nice when things are consistent, because notice that adding two whole numbers

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returns a whole number, you saw this from adding the Enten long values and just the same adding to

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decimals gives a decimal.

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You saw this for the double value.

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It's always nice to see a pattern because it makes coding easier when you can predict what type of return

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value, what type of result you're going to get.

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But don't forget, the plus symbol is special because it goes beyond just numbers.

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We can use it to blend values into a string.

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So we'll start with the bag of sweets now before you do what I'm about to do.

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Just watch me do it first.

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I'll give you time to pause the video in a bit.

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But what I'm going to do is go to the resources article, math operators, resources, and I'm going

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to copy every sentence from part one.

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Pace it at the very bottom.

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Then, while everything is highlighted.

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Press command slashed the comment at all, if you're using a Mac or control slash for windows, and

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this is probably a good place to pause the video and do what I just did.

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All right, by the way, don't mind the front slashes their only comments and have zero effect on your

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code.

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Besides, if you did the workbooks and I encourage you not to skip any of them, you would have already

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encountered comments in any case.

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I'm going to cut and paste the first sentence into a print statement.

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When I put string quotes around it.

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And now look for the placeholder, disconnect the string on both ends.

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And you're going to pace the operation on to the placeholder.

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Put it in brackets, that's really important.

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Then use the plus symbol to blend the result of the math operation into the strike call.

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Compile the code and run it.

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This looks good, plus embeds the number inside the string.

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Now I'm going to minimize the file explorer so that you can see everything I'm doing and notice that

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when blending a math operation into a string, I put it inside brackets.

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I'll tell you why in just a second.

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For now, let's do the same thing for the long and double values.

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Copy each sentence into a string, quote.

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Substitute the operation for the placeholder.

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And then blend that result into the drink.

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And I'm just going to quietly do the same thing for the last one.

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All right.

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Hope that wasn't too hard on compile the code, runit, run it.

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This looks pretty good.

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All right, now let's try removing the brackets, do it for the first one.

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Now recompile the code and run it.

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I'm pretty sure that five plus 10 isn't 500 in ten.

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That's because Java didn't actually add the numbers up, it just connected them.

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If you don't put brackets, things are going to happen from left to right, the string connects to the

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number five.

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So now you're sentences.

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Fred and George collected five.

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And now this new updated sentence connects to the number 10.

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There are new sentences, Fred and George collected five, ten, and then we connect the last string,

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which results in the sentence being Fred and George collected five, 10 suites.

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But when you put brackets, it tells you that this is a math operation, make sure to add these two

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numbers first, then whatever the final result is, can that that into the string?

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Long story short, just to remember to put operations in brackets if you want to display the result

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into a string, that's all.

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All right.

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Recompile the code and run it and you get the result that we expect.

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Go ahead and delete these three comments now.

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All right, let's talk about the minus operator, this one is used to subtract two numbers and the code

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for subtracting stuff is the hyphen.

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So back in our code, we're going to attract every pair of end, long and double values system out print

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line.

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Bag of sweets to mine, his bag of sweets one.

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System systemd out print line.

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Stars in Andromeda, minus stars in the Milky Way.

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And system dot our print line.

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Minus bonus marks.

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OK, let's compile the code.

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And the pattern stays intact, subtracting whole numbers returns a whole number, the supplies to the

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end in long values and subtracting decimals returns a decimal.

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Once again, we can join every member into a string, you're going to copy the sentences down below

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and we're going to copy each one into string quotes.

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One by one.

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Great.

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We're done with that now we're going to disconnect e string where there is a placeholder.

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So here.

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Once you do that, substitute each placeholder at the operation whose return value we want to blend

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into the string.

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And notice that I'm putting each math operation inside brackets, if you don't do that, you'll get

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an error.

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So, yeah, like I said before, if you're trying to blend the result of an operation into a string,

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whatever the operation is, put it in brackets and you should be good.

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All right, now recompile the code and run it.

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Looks good.

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The next operative we can talk about is the multiplication operator, which we use to multiply numbers

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and encode the symbol to multiply numbers as the asterisk.

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So we're going to multiply the intense and double values system, dot out, dot print line.

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Bag of sweets, one times, bag of sweets to.

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We'll do the same thing here.

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Front line test score.

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Times bonus marks.

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We're in a compiler code.

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Then run it.

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And the pattern is strong because once again, multiplying whole numbers returns a whole number and

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multiplying decimals preserves the decimal.

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And once again, trying to connect each result into a string, so we'll copy these sentences into street

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books.

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One by one.

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And we're going to substitute each placeholder with the results for multiplying each pair of numbers.

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All right, that is that you can go out and compile the code and run its.

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And our storyline is really developing.

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You're likely wondering why and multiply the long values, and that's because multiplying two billion,

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500 million by a one trillion, as I calculate it, equals to sextillion 500 quintillion.

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That's a lot of illions.

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And the range for long variables is nine quintillion, so even long can't store that big of a number,

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and if you were to try to perform this multiplication, it wouldn't work because Java is just going

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to return a random number.

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In any case, the last operation we're going to talk about is the division operator, and it's represented

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by the front.

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And we can use it to divide numbers.

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We're going to start with the end and long values system output line, bag of sweets, too, divided

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by a bag of sweets one.

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And once again, system, dot, dot, print line.

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Stars in Andromeda, divided by the stars in the Milky Way.

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Compile this code.

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And run it and as I expected, dividing whole numbers returns a whole number.

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We see this through the end and long values.

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All right, now we'll divide the double values.

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System not out front line test score divided by bonus marks.

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And like always, double preserves the decimal places, no matter what operation you're using.

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All right, well, unless they going to do before we wrap up this video's to connect each number to

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a string.

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So, as always, copy each sentence into a string, quote.

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One by one.

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Take your time.

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Once you do delete the comments and now we're going to replace each placeholder with the result of each

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division.

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All right, we can go back and compile the code.

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And runit.

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Great stuff.

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We created quite the storyline, and if you feel like things were getting repetitive, this means you're

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getting used to it, which is very good.

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And so in this lesson, we used four of the nine math operators, you also saw a very nice pattern.

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A math operation between whole numbers will always return a whole number and a math operation between

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decimals will always preserve the decimal.

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And it's nice to see this pattern because it makes coding easier when you understand how things are

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going to behave.

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We saw this pattern when we applied the first four operators and now I'm going to show you how to use

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the remaining five.