Week 2

Question 1

Objects are ‘____’ - ‘____’ pairs

Answer 1

key-value

Question 2

Write a for loop that counts to 50 by 5.

Answer 2

for (i = 0; i < 51; i += 5){
console.log(i)
}

Question 3

What are the three parts needed for a for loop?

Answer 3

1. ) Initialization
2. ) Stopping condition
3. ) Iteration statement

Question 4

Write a for in loop that console logs each of the values in the following object.
let pet = { 
name: "Finn", 
breed: "Shiba Inu", 
age: 2, 
goodBoy: true 
};

Answer 4

let pet = { 
name: "Finn", 
breed: "Shiba Inu", 
age: 2, 
goodBoy: true 
};
for (item in pet) {
  console.log(pet[item])
}

Question 5

How do you invoke or call this function?
function hi( ) {
console.log('Hello')
}

Answer 5

hi( )

Question 6

Write and invoke a function that counts down from 10 to 0.

Answer 6

function countDown( ) {
  for (i = 10; i >= 0; i--)
  console.log(i)
}
countDown( )

Question 7

Write a for in loop that console logs each item in the following array.
let seasons = ['spring', 'summer', 'autumn', 'winter'];

Answer 7

let seasons = ['spring', 'summer', 'autumn', 'winter'];
for (s in seasons){
  console.log(seasons[s])
}

Question 8

Write a function that accepts the parameter food and console logs “My favorite food is …” using the parameter.

Answer 8

function favFood(food){
  console.log(`My favorite food is ${food}.`)
}
favFood('sushi')

Question 9

Write a function that takes in the parameters crust, sauce, cheese, and topping to build a pizza. Have the function console log your pizza order.

Answer 9

function pizza(crust, sauce, cheese, topping){
  console.log(`I would like a pizza with ${crust} crust, ${sauce}, ${cheese}, and ${topping}.`)
}
pizza('thin', 'marinara', 'mozarella', 'olives')

Question 10

What does the keyword “Return” do?

Answer 10

It brings data out of the function to make it accessible in a wider scope.

Question 11

In the following for loop what is i = 1?

for (i = 1; i <= 10; i++) {
console.log(i)
}

Answer 11

The initialization

In this case it set the variable of i to 1 initially

Question 12

In the following for loop what is i <= 10?

for (i = 1; i <= 10; i++) {
console.log(i)
}

Answer 12

The stopping condition

In this case the for loop will not stop until is is no longer less than or equal to 10

Question 13

In the following for loop what is i++?

for (i = 1; i <= 10; i++) {
console.log(i)
}

Answer 13

The iteration statement

In this case it is saying that the variable i will be incremented by one each time to loop runs.

Question 14

For the following array write a for of loop that console logs “Super Mario” before each of the items.

let games = [64, “Sunshine”, “Galaxy”, “Odyssey”];

Answer 14

let games = [64, “Sunshine”, “Galaxy”, “Odyssey”];

for (game of games) {
console.log(“Super Mario”, game)
}

Question 15

What data type is the following:
let colors = ['blue', 'green', 'purple']

Answer 15

Array

Question 16

What data type is the following:
let colors = {'blue', 'green', 'purple'}

Answer 16

Object

Question 17

What will be console logged?
let dogs = ['Husky', 'Shiba Inu', 'Beagle', 'Dalmatian']
console.log( dogs[1] )

Answer 17

Shiba Inu

Question 18

What index number do arrays start at?

Answer 18

0

Question 19

Which array method will append something to the end of an array?

Answer 19

.push( )

Example Usage: 
let dogs = ['Husky', 'Shiba Inu', 'Beagle', 'Dalmatian'];
dogs.push('Golden Retriever');

Question 20

Which array method can be used to cut something out of an array and add something else?

Answer 20

.splice( )

Example Usage:
let dogs = ['Husky', 'Shiba Inu', 'Beagle', 'Dalmatian']
dogs.splice(0, 1, 'Corgi')
//This will remove Husky and replace it with Corgi

Question 21

The array method .splice( ) takes in three parameters. What is the purpose of each of these three parameters?

Answer 21

Array.splice(position, how many to cut, what to add in that location)

Question 22

What array method can be used to remove the last element of an array?

Answer 22

.pop( )

Example Usage:
let characters = ['Mario', 'Luigi', 'Yoshi', 'Peach']
characters.pop( )
//This will remove Peach

Question 23

What array method can be used to remove the first item of an array?

Answer 23

. shift( )

Example Usage: 
let characters = ['Mario', 'Luigi', 'Yoshi', 'Peach']
characters.shift( )
//This will remove Mario

Question 24

What will happen in the following code:
let characters = ['Mario', 'Luigi', 'Yoshi', 'Peach']
characters.unshift('Bowser', 'Wario')

Answer 24

It will add Bowser and Wario to the beginning of the array

[‘Bowser’, ‘Wario’, ‘Mario’, ‘Luigi’, ‘Yoshi’, ‘Peach’]

Question 25

What are the three arguments for a forEach( )

Answer 25

1. ) currentValue = the current element being processed in the array
2. ) index = the index of the current element being processed
3. ) array = the array the forEach method was called upon

Question 26

What is the syntax for a forEach( ) that will console log each of the items in this array?
let characters = ['Mario', 'Luigi', 'Yoshi', 'Peach']

Answer 26

characters.forEach(c => { console.log(c); })

Question 27

What will this console log?
let food = [‘Pizza’, ‘Pasta’, ‘Hamburger’, ‘Chips’, ‘Ice Cream’]
console.log(food.length)

Answer 27

5

Question 28

How would you step through this object and console log ‘fire’?

let pokemon = {
name: 'Bulbasaur',
id: 1,
type: ['grass', 'poison'],
weakness: ['psychic', 'flying', 'fire', 'ice'],
evolvesTo: 'Ivysaur',
description: 'A strange seed was planted on its back at birth. The plant sprouts and grows with this Pokémon.' 
}

Answer 28

console.log(pokemon.weakness[2])

Question 29

What does JSON stand for?

Answer 29

JavaScript Object Notation