Loop method for infinite loops in Ruby - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of a simple infinite loop with break

What is the output of this Ruby code?

Ruby

count = 0
loop do
  puts count
  count += 1
  break if count == 3
end

A

0
1
2

B

0
1
2
3

C

1
2
3

D No output, infinite loop

💡 Hint

The loop stops when count reaches 3, so it prints before breaking.

The loop prints count starting at 0, increments it, and breaks when count equals 3. So it prints 0, 1, 2 and then stops.

❓ Predict Output

intermediate

Loop method with next keyword

What will this Ruby code print?

Ruby

i = 0
loop do
  i += 1
  next if i.even?
  puts i
  break if i >= 5
end

A No output, infinite loop

B

2
4
6

C

1
2
3
4
5

D

1
3
5

💡 Hint

The next keyword skips even numbers.

The loop increments i, skips printing if i is even, prints odd numbers, and stops when i reaches 5.

🔧 Debug

advanced

Identify the error in this infinite loop

What error does this Ruby code produce?

Ruby

loop do
  puts "Hello"
  break if false
end

A RuntimeError: break from proc-closure

B SyntaxError

C No error, infinite loop printing "Hello" forever

D NameError

💡 Hint

The break condition is always false, so the loop never stops.

The break condition is false, so the loop never breaks and prints "Hello" forever without error.

🧠 Conceptual

advanced

Behavior of loop with return inside

What is the value of variable result after running this Ruby code?

Ruby

result = loop do
  break 42
end

A 42

B nil

C true

D Raises an error

💡 Hint

The break keyword can return a value from the loop.

In Ruby, break can return a value from the loop, so result gets the value 42.

❓ Predict Output

expert

Output of nested loops with break and next

What is the output of this Ruby code?

Ruby

i = 0
loop do
  i += 1
  j = 0
  loop do
    j += 1
    break if j > 2
    next if j == 1
    puts "i=#{i}, j=#{j}"
  end
  break if i >= 2
end

A No output, infinite loop

B

i=1, j=2
i=2, j=2

C i=1, j=2

D

i=1, j=1
i=1, j=2
i=2, j=1
i=2, j=2

💡 Hint

The inner loop skips j=1 and breaks after j>2; outer loop runs twice.

For each i (1 and 2), inner loop increments j from 1 to 3. It skips printing when j=1, prints when j=2, then breaks when j>2. So output lines are for j=2 for i=1 and i=2.