Stacks:
Question 1: Implement a function is_balanced(expression) that takes a string containing parentheses, curly braces, and square brackets,and determines whether the expression is balanced.
An expression is considered balanced if each opening bracket has a corresponding closing bracket in the correct order.
sample input =
expression1 = "([]{})" expression2 = "([)]" print(is_balanced(expression1)) # Output: True print(is_balanced(expression2)) # Output: False
Sequences (Lists/Tuples):
Question 2: Write a function remove_duplicates(sequence) that takes a sequence (list or tuple) and returns a new sequence with duplicates removed while maintaining the original order of elements.
sample input =
input_sequence = [2, 3, 2, 4, 5, 3, 6, 7, 5] result = remove_duplicates(input_sequence) print(result) # Output: [2, 3, 4, 5, 6, 7]
Dictionaries:
Question 3: Implement a function word_frequency(sentence) that takes a sentence and returns a dictionary containing the frequency of each word in the sentence.
Ignore punctuation and consider words in a case-insensitive manner.
sample input =
sentence = "This is a test sentence. This sentence is a test." result = word_frequency(sentence) print(result)