Prefix Count / StartsWith
Problem Statement
Given a list of words, implement a method to check if any word starts with a given prefix.
Example: Words: ["apple","app"], Prefix: "ap" → true, Prefix: "bat" → false
Approach: Trie Prefix Search
Explanation: Traverse the trie along prefix characters. If path exists, return true; else false.
Time Complexity: O(P), P = length of prefix
Space Complexity: O(1)
startsWith(prefix): node = root for char in prefix: if char not in node.children: return False node = node.children[char] return True