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Before we start, did you try solving the workbook yourself?

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If not, please click the link in the resources folder and follow the instructions for this workbook.

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Welcome to Workbook 5.4.

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The first task is to create a function called Sing Public static.

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The function is going to be void because no return type has been specified.

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It's simply going to perform the task of singing when it receives a parameter of type int.

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And the two lines that it's going to sing are the following.

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So first it's going to print.

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The number that gets passed in as a placeholder, followed by some text.

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Break the string.

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Print the number that gets passed in again, followed by another string.

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Looking good.

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We do the same thing over here.

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But you break the string at this placeholder and this time we print whatever number gets passed in minus

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one.

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So basically, imagine that the number 99 gets passed in.

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It would print 99 bottles of beer on the wall, 99 bottles of beer.

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Obviously, once you take one down, then you only have 98 bottles of beer left.

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All right.

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Last thing we need to do is create a for loop that starts at I equals 99.

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So for int I is equal to 99.

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And the reason this workbook is a bit different from the others is because this time we're starting

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high.

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We're starting at 99 and we're going to be stepping downwards.

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This loop is going to keep running so long as I is greater than zero.

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This condition ensures that the last number for which this loop runs ends up equaling one.

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And then we can say I minus, minus.

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So every time this for loop runs, we're going to minus I by one until it eventually is not greater

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than zero and the loop breaks.

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So now we can just say sing, passing an eye every single time the loop runs.

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Let us put one breakpoint over here and visualize the runtime.

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So I start at 99, which is bigger than zero.

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And what that's going to do is call the function saying passing in a value of 99, this is just going

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to print 99 bottles of beer on the wall.

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And then this will print 98 bottles of beer left.

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Okay, now we reach the second run in our loop.

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So before Iowa's 99.

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But after you apply a minus minus, now it's 98.

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So we pass in a value of 98.

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Now we're singing 98 bottles of beer on the wall.

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But after we take one down and pass it around, there are 97 left and this is going to keep going on

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and on until I ends up equaling one.

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So I'm going to fast forward until it reaches that number.

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9876543.

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So now I equals to step inside the function prints two bottles of beer, take one down, pass it around.

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Okay, so now I equals one.

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One is still greater than zero, so the for loop is still going to run.

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Stepping inside the function.

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One bottle of beer on the wall.

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I am minus one zero bottles of beer left.

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So at this point I equals one.

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I am minus.

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Minus is going to update it to zero.

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Zero is not greater than zero.

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So the for loop is going to break.

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And that's it.

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Our song starts with 99 bottles of beer on the wall, and it ends with zero bottles of beer.

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Perfect.