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Alright, so let's try to tackle this challenge step by step. Now, if we look at the flowchart, the first

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question we ask is, is it cleanly divisible by 4?

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If no, then it's definitely not a leap year.

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If yes, then we have to ask more questions.

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So how would we write this in terms of code?

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Well, we'd probably use an if statement to check if the year that were being passed in here is cleanly

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divisible by 4.

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And remember that on a previous lesson, which I linked to here, we learned about the modulo operator

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which gives you the remainder of a division.

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So if the year % 4 is equal to zero, namely if there is no remainder when you divide the

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year by 4, well in that case then it's likely to be a leap year.

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But if it's not even divisible by four, then it's definitely not a leap year.

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So here we could simply return 'Not leap year.'

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So any year that is not divisible by 4, then it's definitely not a leap year.

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But if it is divisible by 4, we still have to check

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is it cleanly divisible by 100?

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Because if no, then it's definitely a leap year,

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but if yes, then we have to check further.

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So the best way to represent that logic is to create another if statement inside this if statement.

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So it's already divisible by 4

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but we have to check whether if it's divisible by 100.

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So if the year % 100 is equal to zero, well, then we have to make some further checks.

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But if it's not, then it's definitely a leap year. So we can return leap year.

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Now, finally, we're in the homestretch and we have to ask ourselves the last question.

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Is it cleanly divisible by 400?

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If no, then it's not a leap year,

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if yes, then it is a leap year.

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So inside this if statement, we're going to ask ourselves one further question:

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if the year is divisible by 400 and that has no remainder, well, then it's definitely a leap year.

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And if that's not true, then it's definitely not a leap year.

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So this is the logic that we saw in the flowchart mapped out with JavaScript code. And going from these

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words to code is actually quite a big jump.

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But going via that middle ground, that flowchart, makes it so much easier to actually map out the logic

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and then converting it into code.

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So I hope you enjoyed that challenge and you managed to get it right.

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And at least if you didn't, you saw how you can use flowcharts to simplify and clarify your own idea

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of the logic, because at the end of the day, the code is easy, but the logic is the part that you

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got to get right first.

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So now if we check our solution, then everything should pass.