Sort_by for custom sorting in Ruby - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to sort the array of numbers in ascending order using sort_by.

Ruby

numbers = [5, 2, 9, 1]
sorted = numbers.sort_by { |n| [1] }
puts sorted

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

Anumbers

Bn

Csorted

Dn.to_s

Attempts:

3 left

💡 Hint

Common Mistakes

Using the whole array instead of the element inside the block.

Using a variable not defined in the block.

The block variable n represents each element. Using n as the key sorts by the number itself.

2fill in blank

medium

Complete the code to sort the array of words by their length using sort_by.

Ruby

words = ["apple", "pear", "banana", "fig"]
sorted = words.sort_by { |word| [1] }
puts sorted

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

Awords.length

Bword

Cword.length

Dword[0]

Attempts:

3 left

💡 Hint

Common Mistakes

Sorting by the whole word instead of its length.

Using the array's length instead of the word's length.

Sorting by word.length sorts words by their length.

3fill in blank

hard

Fix the error in the code to sort people by age using sort_by.

Ruby

people = [{name: "Anna", age: 30}, {name: "Bob", age: 25}]
sorted = people.sort_by { |person| [1] }
puts sorted.map { |p| p[:name] }

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

Aperson[:age]

Bperson.age

Cperson[age]

Dperson['age']

Attempts:

3 left

💡 Hint

Common Mistakes

Using dot notation to access hash keys.

Using string keys instead of symbol keys.

Hashes use symbols as keys accessed with person[:age]. Using person.age causes an error.

4fill in blank

hard

Fill both blanks to sort an array of strings by their last character using sort_by.

Ruby

words = ["cat", "dog", "bird"]
sorted = words.sort_by { |word| word[1][2] }
puts sorted

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

A[-1]

B[0]

C.downcase

D.upcase

Attempts:

3 left

💡 Hint

Common Mistakes

Using [0] to get the first character instead of last.

Not normalizing case, causing unexpected order.

Using word[-1] gets the last character. Applying .downcase ensures case-insensitive sorting.

5fill in blank

hard

Fill all three blanks to sort an array of hashes by the length of the name in descending order using sort_by.

Ruby

people = [{name: "Anna"}, {name: "Elizabeth"}, {name: "Bob"}]
sorted = people.sort_by { |person| [1] [2] [3]1 }
puts sorted.map { |p| p[:name] }

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

Aperson[:name].length

B-

C*

D+

Attempts:

3 left

💡 Hint

Common Mistakes

Sorting ascending instead of descending.

Using dot notation for hash keys.

Missing the negative sign to reverse order.

To sort descending by name length, return negative lengths using - person[:name].length *1. Since sort_by sorts ascending on the returned values, more negative values (longer names) appear first.