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Longest Common Prefix

Intermediate · Write the code · from 50 Python Practice Problems with Instant Answer Checking (Beginner to Advanced)

From the lesson: 50 Python Practice Problems with Instant Answer Checking (Beginner to Advanced)

Fifty problems, each with a code editor and real tests. Write your solution, press Check, and see exactly which cases pass. Stuck? Hints reveal one at a time, and the solution unlocks once you have checked at least once. Your code and progress are saved in this browser.

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Write common_prefix(words) that returns the longest prefix shared by every word in the list (an empty string if there is none, or if the list is empty).

common_prefix(["flower", "flow", "flight"])  ->  "fl"
def common_prefix(words):
pass
Solution unlocks after your first Check

What Check runs

Your code runs first, then each of these lines. The output must match exactly.

RunsExpected output
common_prefix(["flower", "flow", "flight"])'fl'
common_prefix(["dog", "car"])''

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