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Classes & prototypes

Computer Science · JavaScript

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About this practice set

Classes & prototypes is part of Computer Science (JavaScript). Questions are generated with new numbers each time you practise. Levels available: Easy. After you answer, an explanation is shown.

Example questions

A taste of what you will practise. Answers are revealed after you try.

  • Easy

    What does this JavaScript code log? class Cat { constructor() { this.legs = 4; } } const c = new Cat(); console.log(c.legs)