Each as the primary iterator in Ruby - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to print each number in the array.

Ruby

numbers = [1, 2, 3, 4, 5]
numbers.[1] do |num|
  puts num
end

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

Aeach

Bmap

Cselect

Dreduce

Attempts:

3 left

💡 Hint

Common Mistakes

Using map instead of each when you only want to perform an action without creating a new array.

The each method is used to iterate over each element in the array and perform an action, like printing.

2fill in blank

medium

Complete the code to collect squares of numbers using each.

Ruby

numbers = [1, 2, 3, 4]
squares = []
numbers.[1] do |n|
  squares << n * n
end
puts squares

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

Areduce

Bmap

Cselect

Deach

Attempts:

3 left

💡 Hint

Common Mistakes

Using map and expecting the original array to change.

Using each lets you perform actions like adding squares to another array.

3fill in blank

hard

Fix the error in the code to print each key and value from the hash.

Ruby

person = {name: "Alice", age: 30}
person.[1] do |key, value|
  puts "#{key}: #{value}"
end

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

Amap

Beach

Cselect

Dreduce

Attempts:

3 left

💡 Hint

Common Mistakes

Using map which returns a new array instead of iterating for side effects.

The each method is the correct way to iterate over a hash's keys and values.

4fill in blank

hard

Fill both blanks to iterate over an array and print each element with its index.

Ruby

fruits = ["apple", "banana", "cherry"]
fruits.[1].[2] do |fruit, index|
  puts "#{index}: #{fruit}"
end

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

Aeach_with_index

Bmap

Ceach

Dselect

Attempts:

3 left

💡 Hint

Common Mistakes

Using only each without index, or using map which returns a new array.

First call each (which returns the array/enumerator), then chain each_with_index to get both element and index. This demonstrates method chaining with iterators.

5fill in blank

hard

Fill all three blanks to create a hash with word lengths for words longer than 3 letters.

Ruby

words = ["cat", "house", "dog", "elephant"]
lengths = {}
words.[1] do |[2]|
  if [2].length > 3
    lengths[[3]] = [3].length
  end
end
puts lengths

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

Aeach

Bword

Cselect

Dreduce

Attempts:

3 left

💡 Hint

Common Mistakes

Using a transforming method like select or map instead of each for building the hash manually.

Inconsistent block parameter names across the block.

Use each to iterate over the array. Use word consistently as the block parameter name to access each word and conditionally populate the hash with word-length pairs.