def count_words(s): # Write your logic here pass # Prefilled input s = "Hello world, this is a test." print(count_words(s))

class Trie: def __init__(self): # Initialize Trie here pass def insert(self, word): # Insert a word into Trie pass def search(self, word): # Search for a word in Trie pass # Prefilled input trie = Trie() words = ["apple", "app", "apply"] for word in words: trie.insert(word) print(trie.search("app"))

def is_rotation(s1, s2): # Write your logic here pass # Prefilled input s1 = "waterbottle" s2 = "erbottlewat" print(is_rotation(s1, s2))

def longest_palindromic_substring(s): # Write your logic here pass # Prefilled input s = "babad" print(longest_palindromic_substring(s))

def min_window_substring(s1, s2): # Write your logic here pass # Prefilled input s1 = "ADOBECODEBANC" s2 = "ABC" print(min_window_substring(s1, s2))

class TrieNode: def __init__(self): self.children = {} self.word = None class WordSearch: def __init__(self): self.root = TrieNode() def insert(self, word): # Insert words into Trie pass def find_words(self, board, words): # Search words in board using Trie pass # Prefilled input board = [ ["o", "a", "a", "n"], ["e", "t", "a", "e"], ["i", "h", "k", "r"], ["i", "f", "l", "v"] ] words = ["oath", "pea", "eat", "rain"] ws = WordSearch() for word in words: ws.insert(word) print(ws.find_words(board, words))

def generate_permutations(s): # Write your logic here pass # Prefilled input s = "abc" print(generate_permutations(s))

def kmp_search(text, pattern): # Write your logic here pass # Prefilled input text = "ababcabcab" pattern = "abc" print(kmp_search(text, pattern))

class TrieNode: def __init__(self): self.children = {} self.word_list = [] class AutoComplete: def __init__(self): # Initialize Trie here pass def insert(self, word): # Insert word into Trie pass def get_suggestions(self, prefix): # Return words with given prefix pass # Prefilled input ac = AutoComplete() words = ["hello", "hell", "helicopter", "hero", "help", "heap"] for word in words: ac.insert(word) print(ac.get_suggestions("he"))

class TrieNode: def __init__(self): self.children = {} self.freq = 0 class ShortestPrefix: def __init__(self): # Initialize Trie here pass def insert(self, word): # Insert word into Trie and track frequency pass def get_shortest_prefix(self, word): # Return shortest unique prefix pass def find_unique_prefixes(self, words): # Find unique prefixes for all words pass # Prefilled input words = ["dog", "dove", "duck"] sp = ShortestPrefix() for word in words: sp.insert(word) print(sp.find_unique_prefixes(words))