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    • What is JavaScript?
    • Variables: let, const and var
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    • Loops: for and while
    • Challenge: FizzBuzz

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    Modern JavaScript and a project

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    JavaScript

    Control flow · Lesson 13 of 45

    Challenge: FizzBuzz

    The most famous interview question, with conditions and loops.

    8 minutes2 games

    Important

    Only one branch of an if/else if chain runs. Test overlapping cases before broader cases.

    The task: print the numbers 1 to 15, except:

    • multiples of 3 print Fizz instead,
    • multiples of 5 print Buzz,
    • multiples of both print FizzBuzz.

    Interviewers love it because it shows whether you understand the order of conditions.

    Interview question

    Why must the “both” case (15) be checked first?

    Order the lines

    Put the conditions in the right order inside the loop.

    1. Click the lines in the right order

    Exercise

    Write FizzBuzz from 1 to 15.

    Expected output:
    1
2
Fizz
4
Buzz
Fizz
7
8
Fizz
Buzz
11
Fizz
13
14
FizzBuzz
    JavaScript
    for (let i = 1; i <= 15; i++) {
  
}

    Learn more from

    • Wikipedia: Fizz buzzen.wikipedia.org
    • javascript.info: Loops: while and forjavascript.info

    Played 0 of 2 games

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