Simple Autocomplete System

You are tasked with creating a simple autocomplete system using a trie data structure. The system should allow you to insert words and then search for words that start with a given prefix. The input consists of a series of operations: 1. 'INSERT <word>' - Insert a word into the trie. 2. 'SEARCH <prefix>' - Return all words in the trie that start with the given prefix, sorted in alphabetical order. The input will end after the last operation and you must print the search results for each 'SEARCH' operation. Example: INPUT: INSERT apple INSERT app INSERT banana SEARCH app SEARCH a SEARCH b SEARCH x OUTPUT: app apple banana