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In this exercise,

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the goal is to use what you've learned about variables

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to figure out how to switch the value in two variables.

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The idea here is we've got two values

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that is put into the Input pane on lines one and two.

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So the first one, in this case 29,

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is going to be substituted into the variable "a" on line two.

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The second one, 41, is going to be set equal

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to the variable "b" on line three.

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Your goal is to write some code between lines seven and 10

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that can switch those values around

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so that when the print statement runs on lines 12 and 13,

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that it will print a as equal to the value of 41,

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which used to be stored in b 

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and line 15 will print b  and then colon

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and then the value 29,

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which used to be stored in the variable b.

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It is just a switcheroo and you're going have to think

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about how to do this using what you know about variables.

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There's many ways to solve this, but give it a go now.

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All right, so the solution only takes three lines of code

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and I'm going to run through them each one-by-one.

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The first step was to create a third variable

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and this is key to solving this exercise

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because we need some temporary store.

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If we set "c" equal to the value of a,

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right now using the example input,

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c is equal to the word assembly.

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Next, we set a equal to the value of b,

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so a is now equal to "Basic".

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Finally, we set b equal to the value of c

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so that we take that temporary variable,

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grab the value inside and put it into the variable b.

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So now we've switched the values in a and b around

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and we have no longer any use for the value inside c.

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But at this point, the switcheroo is complete

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and when we print out a and b,

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they will show the opposite of what they use to hold.

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So now, given the current example Input, Assembly and Basic,

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we will end up with Basic Assembly being outputted,

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switching the values around.

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So if you needed to make any changes to your code,

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feel free to go back to the previous slide,

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but have a think about why this works

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and how creating variables allow us

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to store values inside them,

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just like boxes when you're moving.