Modify list in-place (mutable demonstration) Dry Run in PYTHON

Modify list in-place (mutable demonstration) is an interactive PYTHON dry run visualizer from the Functions programs section. Study the source code, then use the execution controls to follow each step, variable update, highlighted line, and console output.

This page provides a browser-based dry run with source-code highlighting, auto-scroll, voice narration controls, and execution output for learning the program step by step.

Modify list in-place (mutable demonstration) Program Code

def remove_odds(lst):
    """Remove all odd numbers from list (in-place)"""
    # Iterate backwards to avoid index issues
    for i in range(len(lst) - 1, -1, -1):
        if lst[i] % 2 != 0:
            lst.pop(i)

numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
print(f"Before: {numbers}")
remove_odds(numbers)
print(f"After:  {numbers}")  # Original list modified!

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