Python Coding Challenge - Question with Answer (ID -010426)

Explanation:

1️⃣ Creating the list

clcoding = [[1, 2], [3, 4]]

A nested list (list of lists) is created.

Memory:

clcoding → [ [1,2], [3,4] ]

2️⃣ Copying the list

new = clcoding.copy()

This creates a shallow copy.

Important:

Outer list is copied

Inner lists are NOT copied (same reference)

👉 So:

clcoding[0]  → same object as new[0]

clcoding[1]  → same object as new[1]

3️⃣ Modifying the copied list

new[0][0] = 99

You are modifying inner list

Since inner lists are shared → original also changes

👉 Now both become:

[ [99, 2], [3, 4] ]

4️⃣ Printing original list

print(clcoding)

Because of shared reference, original is affected

👉 Output:

[[99, 2], [3, 4]] 

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