Find/detect for first match in Ruby - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to find the first even number in the array.

Ruby

numbers = [1, 3, 4, 6, 7]
first_even = numbers.[1] { |n| n.even? }
puts first_even

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

Aeach

Bselect

Cmap

Dfind

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'select' returns all matching elements, not just the first.

Using 'map' transforms all elements, not find one.

The find method returns the first element for which the block returns true.

2fill in blank

medium

Complete the code to detect the first word longer than 5 characters.

Ruby

words = ['apple', 'banana', 'pear', 'grape']
long_word = words.[1] { |word| word.length > 5 }
puts long_word

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

Areject

Bselect

Cdetect

Deach

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'select' returns all matching elements, not just the first.

Using 'reject' returns elements that do not match.

detect is an alias for find and returns the first element matching the condition.

3fill in blank

hard

Fix the error in the code to find the first number divisible by 3.

Ruby

nums = [2, 4, 6, 9, 12]
result = nums.[1] { |num| num % 3 == 0 }
puts result

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

Afind

Bmap

Cselect

Deach

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'select' returns an array, not a single element.

Using 'map' transforms elements instead of filtering.

find returns the first element matching the condition; select returns all matching elements.

4fill in blank

hard

Fill both blanks to create a hash of words and their lengths, but only for words longer than 4 characters.

Ruby

words = ['cat', 'elephant', 'dog', 'giraffe']
lengths = words.select { |word| word.length > 4 }.map { |word| [[1], [2]] }.to_h

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

Aword

Bword.length

Cword.size

Dlen

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'len' which is not a Ruby method.

Using 'word.size' is valid but not the expected answer here.

The key should be the word itself, and the value should be its length using word.length.

5fill in blank

hard

Fill both blanks to find the first number greater than 10 and print it.

Ruby

numbers = [4, 7, 12, 15, 3]
first_big = numbers.[1] { |n| n [2] 10 }
puts first_big

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

Afind

B>

Dselect

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'select' returns all matching numbers, not just the first.

Putting an extra method after puts causes errors.

find locates the first number greater than 10 using the '>' operator. The last blank is empty because puts already prints the value.