Map/collect for transformation in Ruby - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to transform each number by doubling it using map.

Ruby

numbers = [1, 2, 3, 4]
doubled = numbers.[1] { |n| n * 2 }
puts doubled.inspect

Drag options to blanks, or click blank then click option'

Aselect

Bmap

Ceach

Dcollect

Attempts:

3 left

💡 Hint

Common Mistakes

Using each which returns the original array without changes.

Using select which filters elements instead of transforming.

The map method transforms each element and returns a new array with the results.

2fill in blank

medium

Complete the code to convert all strings in the array to uppercase using collect.

Ruby

words = ['apple', 'banana', 'cherry']
upcased = words.[1] { |word| word.upcase }
puts upcased.inspect

Drag options to blanks, or click blank then click option'

Aeach

Bselect

Ccollect

Dreject

Attempts:

3 left

💡 Hint

Common Mistakes

Using each which does not return a transformed array.

Using select which filters elements.

The collect method is an alias for map and transforms each element.

3fill in blank

hard

Fix the error in the code to correctly transform numbers by adding 5 using map.

Ruby

nums = [10, 20, 30]
result = nums.[1] { |num| num + 5 }
puts result.inspect

Drag options to blanks, or click blank then click option'

Amap

Bselect

Ceach

Dfind

Attempts:

3 left

💡 Hint

Common Mistakes

Using each which does not transform the array.

Using select which filters elements.

map returns a new array with each element transformed. each returns the original array.

4fill in blank

hard

Fill both blanks to create a hash where keys are words and values are their lengths using map.

Ruby

words = ['dog', 'cat', 'bird']
lengths = words.[1] { |word| [word, word.[2]] }.to_h
puts lengths.inspect

Drag options to blanks, or click blank then click option'

Amap

Beach

Clength

Dsize

Attempts:

3 left

💡 Hint

Common Mistakes

Using each which does not return a transformed array.

Using size which also works but is less common than length.

map transforms each word into a key-value pair array. length returns the length of the string.

5fill in blank

hard

Fill all three blanks to transform an array of numbers into a hash with keys as strings and values as squares.

Ruby

nums = [1, 2, 3]
squares = nums.[1] { |n| [n.[2].to_s, n [3] 2] }.to_h
puts squares.inspect

Drag options to blanks, or click blank then click option'

Amap

Bto_s

C**

Deach

Attempts:

3 left

💡 Hint

Common Mistakes

Using each which does not transform the array.

Using * instead of ** for squaring.

map transforms each number into a key-value pair. to_s converts the number to a string key. ** squares the number.