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Looping one step too far

🐛 Fix the bug Topic: lists Difficulty: easy Free

What this problem practises

Lists are mutable and assigned by reference. That one fact explains most list bugs: aliasing between what look like "copies", append() and sort() returning None, and slice boundaries that disagree with the index arithmetic.

This is a fix-the-bug problem: a short program is given in its broken state, and the task is to repair the code so it produces the required output. The interactive editor runs your fixed version in the browser and checks it for you — no setup, no local interpreter.

Difficulty: easy — the fix or the trick is normally a single line, and a careful read should be enough.

The challenge

This should print every item in the list, but crashes partway through. Fix it.

The code runs in PyDebug’s in-browser compiler. Open the problem, run the snippet, watch the exact error or output, and keep iterating until it is right. Signed-in solves count toward XP and your daily streak.

The error it raises

Run the broken snippet and Python stops with this exact error: IndexError: list index out of range. Match it to the Python errors guide, then repair the line that produced it — knowing the message is half the fix.

The snippet

The interactive editor pre-fills exactly this code, broken and ready to repair:

fruits = ["apple", "banana", "cherry"]
for i in range(4):
    print(fruits[i])
Solve it in the interactive editor →

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