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Solution: Stream of Characters

Explore how to design a data structure that processes a character stream and checks if any suffix matches a word from a given list. Understand how reversing words and using a Trie combined with a deque allows efficient suffix matching. Learn the construction and query operations with time and space complexity insights.

Statement

Design a data structure that processes a stream of characters and, after each character is received, determines if a suffix of these characters is a string in a given array of strings words.

For example, if words = ["dog"] and the stream adds the characters ‘d’, ‘c’, ‘a’\text{`d', `c', `a'}, and ‘t’\text{`t'} in sequence, the algorithm should detect that the suffix "cat" of the stream "dcat" matches the word "cat" from the list.

So, for words, the goal is to detect if any of these words appear as a suffix of the stream built so far. To accomplish this, implement a class StreamChecker:

  • Constructor: Initializes the object with the list of target words.

  • boolean query(char letter): Appends a character to the stream and returns TRUE if any suffix of the stream matches a word in the list words.

Constraints:

  • 11\leq words.length ...