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Exercise 149

Implement Trie 25 XP Medium

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Implement a Trie with insert, search, and startsWith methods.

Search returns True only if the word exists AND was inserted (is_end=True). StartsWith returns True if any word starts with the prefix.

💡 Pro tip: Understand this problem deeply — don't just memorize the code. Try explaining the approach out loud as if teaching a friend. If you can explain it simply, you truly understand it!

📋 Instructions

Implement Trie and test: insert 'apple', search 'apple' (True), search 'app' (False), startsWith 'app' (True), insert 'app', search 'app' (True).

search: walk to end, return is_end. startsWith: walk to end, return True if all chars found.

🧪 Test Cases

Input

t.search('apple')

Expected

True

Boolean check

Input

t.search('app')

Expected

False

Boolean check

Input

t.startsWith('app')

Expected

True

Boolean check

Input

t.search('app')

Expected

True

Boolean check

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main.py

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Output

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