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This lesson is going to be about JavaScript function recursion, and what it does is it gives us a quick

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ability to create a quick loop of content.

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Essentially what it's doing is it's a function calling itself from within itself.

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And this is a really neat function that we can apply and have this functionality.

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In this case, what we're doing is we're creating a loop.

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So we've got a function.

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We're passing in an argument.

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So the value of this parameter is X, and we're checking to see if X is greater than or equal to 10.

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And if it is, we add return and which will end the loop.

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Otherwise we log it out into the console, thought our recursive call, which is calling itself.

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So it's taking X and it's adding one to it.

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So the next time that it comes through exhusband increment add value and it will continue to loop through

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until it meets this condition and it can finally return the function.

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So the challenge within this lesson is to create a function that asks for a guess from the user and

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uses the guests value to compare to see if the user guessed correctly and let them know if it's correct

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or incorrect and then call the function again until you get the correct guess.

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So I know this is probably a little bit annoying of a function, but it shows the usefulness of creating

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recursion.

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And you can also use a territory operator to provide a suggestion for the next guess if the user is

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wrong.

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So we can take a look and we can see if the number is larger or smaller and make a suggestion to the

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user.

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I'll give you a quick sneak peek at the solution and you can pause the video and I'll walk you through

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the solution coming up.

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So if you had an opportunity to try this out and this is taking code that we've done earlier and applying

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it within larger block of code, so we start out with creating a secret number.

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So this is the number that we want the user to be able to guess and declaring another variable that

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can hold the guests value so that we can guess this value multiple times and then we need to invoke

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the function.

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So you can call the function guesser.

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So create a function.

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And the function is named guesser.

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So we're going to start out with a prompt of a guest for the function so we can set guests to be equal

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to whatever the value of promptness, and we're going to ask the user to guess the number.

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So this is guessing that secret number and hopefully for them, for their sake, they do.

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Guess five correctly, because unfortunately for them, this function won't end until they do get set

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correctly.

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So take a look at the value of guests.

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And we're also going to turn that, make sure that it is a number that they are guessing.

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So guess number.

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So we make sure that it is a number by using the data type conversion.

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So converting it into a guess and then we can check to see if the value of number is equal to the secret

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number.

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And if it is, then we can output a message that they guessed correctly.

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So in the console will output a message.

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You got it.

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And then to break out of our recursion, we're going to do a return.

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And if they didn't guess correctly, then we're just launching guesser.

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So this is a function guesser.

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And what this is going to do is it's going to create a prompt.

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The prompt is going to ask our user to guess a number.

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We're going to take that response value, turn it into a number and then check to see if guess number

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is equal to the secret number.

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And if it is, then we can end the function and we can move along.

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Otherwise we're just going to keep keep the user guessing.

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So try that out and we'll guess three.

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We see it's wrong.

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Six, it's wrong.

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Seven, it's wrong.

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Five, you got it.

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And it ends the function.

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So we did have a second part to this.

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And this is if you want some bonus points, you can go ahead and add this in.

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So this is taking some conditions and giving a hint to the user for the user.

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So we know that they've got it wrong here and we can console log out, taking a look at the condition

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to see if guess number is less than the secret number and we can put that into the console.

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So if we get the wrong number, we get true or we get false.

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We get a boolean value from this statement and we can apply this into a condition, trinary condition

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where we can check to see.

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So creating a message we can check to see if the guess number is less than the secret number.

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Otherwise we're going to tell them to go lower wrong.

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And then let's add the message.

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So this will give us a hint as to which direction the gas needs to be.

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So it gets to go higher.

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Yes, eight go lower, six go lower, four go higher.

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And then five, we got it right.

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So so you can add some additional functionality into your.