21. Trie (Prefix Tree)

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Example 1:

Input:

operations = ["Trie", "insert", "search", "search", "startsWith", "insert", "search"], words = [[], ["apple"], ["apple"], ["app"], ["app"], ["app"], ["app"]]

Output: [null, null, true, false, true, null, true]

Explanation: Demonstrates insertion, searching for existing and non-existing words, and prefix searching.

Example 2:

Input: operations = ["Trie", "insert", "search", "startsWith"], words = [[], ["a"], ["a"], ["a"]]

Output: [null, null, true, true]

Explanation: Tests with a single character word/prefix.

Constraints:

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Time Complexity

O(m)

Space Complexity

O(n*m)