JavaScript Arrays Lab

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Introduction

This lab provides an opportunity to practice defining, accessing and manipulating arrays.

Note: Feel free to reference the arrays lesson, collaborate, google, etc.

Setup & Instructions

For the exercises in this lab, create a JavaScript REPL from repl.it -- you can name it "JavaScript Arrays lab".

Exercise

Copy the exercises below into the included script.js file and code away!

Please note: You will most likely need to comment out the console.logs for the exercises you've yet to complete to avoid getting a Reference Error

/*
Exercise 1:
  - Define an empty array named foods
*/

// Exercise 1 has been completed for you...

const foods = [];

console.log('Exercise 1 Result: ', foods);

/*
Exercise 2:
  - Add the strings 'pizza' & 'cheeseburger' to the foods array such that 'pizza' comes before 'cheeseburger'.
*/

// Complete Exercise 2 below...



console.log('Exercise 2 Result: ',  foods);

/*
Exercise 3:
  - Add the string 'taco' to the foods array so that 'taco' is the first food in the array.
*/

// Complete Exercise 3 below...



console.log('Exercise 3 Result: ', foods);

/*
Exercise 4:
  - Access the string 'pizza' (based upon its known position) in the foods array and assign to a variable named favFood.
*/

// Complete Exercise 4 below...



console.log('Exercise 4 Result: ', favFood);

/*
Exercise 5:
  - Insert the string 'tofu' in the foods array between 'pizza' & 'cheeseburger'
*/

// Complete Exercise 5 below...



console.log('Exercise 5 Result: ', foods);

/*
Exercise 6:
  - Replace the string 'pizza' in the foods array with the strings 'sushi' & 'cupcake'.
*/

// Complete Exercise 6 below...



console.log('Exercise 6 Result: ', foods);

/*
Exercise 7:
  - Use the slice method on the foods array to create a new array containing 'sushi' & 'cupcake'.
  - Assign the new array to a variable named yummy.
*/

// Complete Exercise 7 below...



console.log('Exercise 7 Result: ', yummy);

/*
Exercise 8:
  - Using the indexOf method on the foods array, assign the index of the 'tofu' string to a variable named soyIdx.
*/

// Complete Exercise 8 below...



console.log('Exercise 8 Result: ', soyIdx);

/*
Exercise 9:
  - Assign to a variable named allFoods the result of joining the strings in the foods array such that the result is the following single string:
    'taco -> sushi -> cupcake -> tofu -> cheeseburger'
*/

// Complete Exercise 9 below...



console.log('Exercise 9 Result: ', allFoods);

/*
Exercise 10:
  - Assign a boolean to a variable named hasSoup depending upon whether or not the foods array includes the string 'soup'.
*/

// Complete Exercise 10 below...



console.log('Exercise 10 Result: ', hasSoup);

/*
Exercise 11:
  - Use the forEach method to iterate through the provided nums array and add each odd number to a new array named odds.
  - Hint: Initialize the odds variable to an empty array before the iteration.
*/

const nums = [100, 5, 23, 15, 21, 72, 9, 45, 66, 7, 81, 90];

// Complete Exercise 11 below...



console.log('Exercise 11 Result: ', odds);

/*
Exercise 12:
  - Use the forEach method to iterate through the same nums array and add the number to arrays named fizz, buzz and/or fizzbuzz based upon the following:
  	- Add to the fizz array if the number is evenly divisible by 3.
  	- Add to the buzz array if the number is evenly divisible by 5.
  	- Add to the fizzbuzz array if the number is evenly divisible by 3 & 5.
*/

// Complete Exercise 12 below...



console.log('Exercise 12 Results:');
console.log('  fizz:', fizz);
console.log('  buzz:', buzz);
console.log('  fizzbuzz:', fizzbuzz);

/*
Exercise 13:
  - Given the below numArrays array of arrays (two-dimensional array), assign the last nested array to a variable named numList.
  - Assume you don't know how many nested arrays numArrays contains.
*/

const numArrays = [
	[100, 5, 23],
	[15, 21, 72, 9],
	[45, 66],
	[7, 81, 90]
];

// Complete Exercise 13 below...



console.log('Exercise 13 Result: ', numList);

/*
Exercise 14:
  - Given the above numArrays array, access the number 66 and assign to a variable named num.
*/

// Complete Exercise 14 below...



console.log('Exercise 14 Result: ', num);

/*
Exercise 15:
  - Given the above numArrays array, use nested forEach methods to sum up all the numbers contained within numArrays and assign to a variable named total.
  - Hint: Be sure to declare and initialize the total variable before the iterations.
*/

// Complete Exercise 15 below...



console.log('Exercise 15 Result: ', total);

Additional Resources

MDN Arrays