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Kotlin-based LeetCode algorithm problem solutions, regularly updated
1032\. Stream of Characters
Hard
Design an algorithm that accepts a stream of characters and checks if a suffix of these characters is a string of a given array of strings `words`.
For example, if `words = ["abc", "xyz"]` and the stream added the four characters (one by one) `'a'`, `'x'`, `'y'`, and `'z'`, your algorithm should detect that the suffix `"xyz"` of the characters `"axyz"` matches `"xyz"` from `words`.
Implement the `StreamChecker` class:
* `StreamChecker(String[] words)` Initializes the object with the strings array `words`.
* `boolean query(char letter)` Accepts a new character from the stream and returns `true` if any non-empty suffix from the stream forms a word that is in `words`.
**Example 1:**
**Input** ["StreamChecker", "query", "query", "query", "query", "query", "query", "query", "query", "query", "query", "query", "query"] [[["cd", "f", "kl"]], ["a"], ["b"], ["c"], ["d"], ["e"], ["f"], ["g"], ["h"], ["i"], ["j"], ["k"], ["l"]]
**Output:** [null, false, false, false, true, false, true, false, false, false, false, false, true]
**Explanation:**
StreamChecker streamChecker = new StreamChecker(["cd", "f", "kl"]);
streamChecker.query("a"); // return False
streamChecker.query("b"); // return False
streamChecker.query("c"); // return False
streamChecker.query("d"); // return True, because 'cd' is in the wordlist
streamChecker.query("e"); // return False
streamChecker.query("f"); // return True, because 'f' is in the wordlist
streamChecker.query("g"); // return False
streamChecker.query("h"); // return False
streamChecker.query("i"); // return False
streamChecker.query("j"); // return False
streamChecker.query("k"); // return False
streamChecker.query("l"); // return True, because 'kl' is in the wordlist
**Constraints:**
* `1 <= words.length <= 2000`
* `1 <= words[i].length <= 2000`
* `words[i]` consists of lowercase English letters.
* `letter` is a lowercase English letter.
* At most 4 * 104
calls will be made to query.