Split and join methods in Ruby - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of splitting a string with multiple spaces

What is the output of this Ruby code?

Ruby

text = "apple  banana   cherry"
result = text.split(" ")
puts result.inspect

A ["apple", " banana", " cherry"]

B ["apple", "banana", "cherry"]

C ["apple banana cherry"]

D ["apple", "", "banana", "", "", "cherry"]

💡 Hint

The split method with a space splits exactly on each space character.

Using split(" ") splits the string at every single space, so multiple spaces create empty strings in the array.

❓ Predict Output

intermediate

Joining array elements with a custom separator

What is the output of this Ruby code?

Ruby

arr = ["red", "green", "blue"]
result = arr.join("-")
puts result

A red green blue

B red,green,blue

C red-green-blue

D redgreenblue

💡 Hint

The join method uses the string you give as a separator between elements.

The join method combines array elements into one string, placing the given separator between them.

🔧 Debug

advanced

Why does this split produce an empty first element?

Consider this Ruby code. Why does the first element of the result array become an empty string?

Ruby

text = ",one,two,three"
result = text.split(",")
puts result.inspect

A Because the string starts with the separator, split creates an empty string before the first comma.

B Because split removes the first element if it is empty.

C Because split ignores separators at the start of the string.

D Because split treats commas as part of the first element.

💡 Hint

Think about what happens before the first comma.

When the string starts with the separator, split returns an empty string for the part before the first separator.

❓ Predict Output

advanced

Splitting with limit parameter

What is the output of this Ruby code?

Ruby

text = "a,b,c,d"
result = text.split(",", 3)
puts result.inspect

A ["a", "b", "c", "d"]

B ["a", "b", "c,d"]

C ["a,b", "c", "d"]

D ["a", "b,c", "d"]

💡 Hint

The limit parameter controls how many parts the string is split into.

With limit 3, split divides the string into at most 3 parts, so the last part contains the rest of the string.

🧠 Conceptual

expert

Effect of split and join on string with multiple separators

Given the Ruby code below, what is the final output?

Ruby

text = "one,,two,,,three"
parts = text.split(",")
joined = parts.join(",")
puts joined

A one,,two,,,three

B one,two,three

C one,,two,,three

D one,two,,three

💡 Hint

Think about how split handles consecutive separators and what join does with empty strings.

Split creates empty strings for consecutive commas, and join puts commas back between all elements, preserving the original pattern.