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A nested loop is a loop inside of another loop.

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This for a loop is going to repeat code three times, but what if I placed another loop inside of it,

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one that also runs code three times?

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How many times is hello going to Prince?

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Before I break it down for you, I encourage you to pause, take out a pen and paper and try to trace

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the runtime of the code that I'm about to re display.

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I hope you figure it out.

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Hopefully that went well in this lesson, you're going to learn to use nested loops.

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First thing you need to do is create a new class inside your Section five folder.

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This file is going to be called nested loops and make sure the class has a main method.

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The nested loops as an outer loop and an inner loop.

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The outer loop is the big loop and the inner loop is the smaller loop inside.

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This print statement is going to run nine times because each pass from the outer loop is going to run

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the inner loop to completion.

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The first pass is going to run the inner loop three times.

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The second pass is going to run the inner loop three times.

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And the third pass is going to run the inner loop three times.

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In total, the nested loop ran nine times.

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So a nested loops Java, I'm going to start by making a loop that runs exactly three times the loop

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starts with the counter, I equaling zero, the loop is going to keep running as long as is less than

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three.

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And after each run, we're going to increase the counter value by one.

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And so every time this loop runs, we're going to print the value of the counter during that run, so

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system that out the print line run and I'll connect the counter value during that run, I.

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And great, we printed the counter during the first run, second run and third run.

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Now I'm going to write a for loop inside the current one.

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The loop starts with the counter J equalling zero.

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The loop is going to keep running as long as J is less than three and after each run, we're going to

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increase the counter J value by one.

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And every time this loop runs, I'm going to print the counter value.

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And before I explain what's going to happen, it might be worth it to just run the code and see the

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output.

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And as I expect, every pass from the outer loop runs the inner loop to completion.

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The outer loop started equals zero, which is less than three, so the outer loop runs Prince, the

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counter value for that run, eventually reaching the inner loop inside and now the inner loop is going

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to start a J.

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Equals zero, which is less than three.

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It's going to run print the counter value for that run.

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And the inner loop is just going to keep running until Jay isn't less than three anymore.

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And once that happens, the inner breaks and in turn that erupts up all the code for the first run of

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the outer loop.

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Now I equals one.

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And this process is just going to keep repeating until the outer loop breaks.

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The big picture here is that each run from the outer loop is going to run the inner loop to completion.

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Now, I'm going to let this play in case you need more time to visualize what's going on.

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But if you feel comfortable what we talked about so far, then feel free to skip ahead in the video.

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OK, so what are some applications of nested loops, nested loops are useful when you're working with

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2D arrays, you haven't learned about arrays yet, so you're not going to see nested loops for the remainder

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of this section, but they are going to come back in the next section.

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I can promise you that.

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All righty, let's recap in this lesson, you learned how nested for loops are run.

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And a nested loop has an outer loop and an inner loop, each pass from the outer loop runs the inner

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loop to completion.

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And that's really it, good job you covered everything there is to know about loops in Java.

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It's time to build the sections Project Pocari Areto.

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It's almost poker if you feel confident.

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But we talked about so far, then you can feel free to skip to the next video.

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But if you want to visualize the nested loop one more time slowed down without me speaking over it,

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then I'll play it for the next two minutes.

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All right.

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See you soon.