The following code is intended to create an array of 3 separate empty arrays. What is the problem?

medium📝 Debug Q14 of 15

Ruby - Arrays

arr = Array.new(3, [])
arr[0] << 1
puts arr.inspect

A[[1], [1], [1]]

B[[1], [], []]

C[[], [], []]

DSyntaxError

Step-by-Step Solution

Solution:

Step 1: Understand Array.new with default object
Using Array.new(3, []) creates 3 references to the same empty array, not 3 separate arrays.
Step 2: Analyze mutation effect
When arr[0] << 1 runs, it adds 1 to the shared array, so all elements show the change.
Final Answer:
[[1], [1], [1]] -> Option A
Quick Check:
Same object repeated causes all elements to change [OK]

Quick Trick: Use block with Array.new for separate objects [OK]

Common Mistakes:

MISTAKES

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