Design a Trie (Prefix Tree)
TriePrefix TreeTree TraversalDFSComposite PatternStrategy Pattern
Design and implement a Trie (Prefix Tree) data structure that efficiently stores and retrieves strings. The Trie should support insert(word), search(word) for exact matches, startsWith(prefix) for prefix matching, autocomplete(prefix) to return all words with a given prefix, delete(word) to remove words, and countWordsWithPrefix(prefix) to count words sharing a prefix. The design should demonstrate understanding of tree structures, character-based edge traversal, prefix matching algorithms, DFS traversal for autocomplete, and efficient word deletion.
What You'll Build
- The Trie must support insert(word) operation that adds a word to the Trie by creating nodes for each character if they don't exist and marking the end of the word.
- The Trie must support search(word) operation that returns true if an exact word exists in the Trie, false otherwise. This requires checking if the word path exists and the last node is marked as end-of-word.
- The Trie must support startsWith(prefix) operation that returns true if any word in the Trie starts with the given prefix, false otherwise.
- The Trie must support autocomplete(prefix) operation that returns a list of all words in the Trie that start with the given prefix, using DFS traversal from the prefix node.
- The Trie must support delete(word) operation that removes a word from the Trie by unmarking the end-of-word flag and removing unnecessary nodes (nodes with no children that aren't end-of-word).
- ...and more
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