Radix trees: insert/search/delete strings in O(h) time.

In a vast digital library, books are organized using a unique cataloging system. The system utilizes a specialized data structure to store and retrieve book titles efficiently. The goal is to design a function that can insert, search, and delete book titles in this catalog while ensuring the operation time complexity remains optimal. The function should be able to handle a large number of book titles and perform operations quickly, making it suitable for a large-scale digital library.

Examples
Input: "test_input_1"
Output: "output_1"
Hints

Radix trees: insert/search/delete strings in O(h) time.

In a vast digital library, books are organized using a unique cataloging system. The system utilizes a specialized data structure to store and retrieve book titles efficiently. The goal is to design a function that can insert, search, and delete book titles in this catalog while ensuring the operation time complexity remains optimal. The function should be able to handle a large number of book titles and perform operations quickly, making it suitable for a large-scale digital library.