Dsa
Trie
Warm-up
Case-Insensitive Registry
A registry stores usernames. A query prefix is typed into a search bar. You need to find if any registered username starts with that prefix, ignoring case (e.g., 'Adm' matches 'admin').
Input Format:
1. An integer N.
2. N registered usernames.
3. A query prefix.
Output Format:
'FOUND' if at least one username matches the prefix (case-insensitive), otherwise 'NOT FOUND'.
Example:
Input:
2
Alice
Bob
al
Output:
FOUND
Key concepts
trienormalizationstrings
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