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Practice Questions
Test your understanding with targeted questions related to the topic.
Question 1
Easy
Define a valid string in the context of parentheses.
💡 Hint: Think about matching pairs.
Question 2
Easy
Provide two examples of valid strings.
💡 Hint: Focus on balanced pairs.
Practice 4 more questions and get performance evaluation
Interactive Quizzes
Engage in quick quizzes to reinforce what you've learned and check your comprehension.
Question 1
What is the definition of a valid parenthesis string?
- A string that is completely empty
- A string where each '(' matches a ')'
- A string with more ')' than '('
💡 Hint: Think about what makes a string valid!
Question 2
True or False: The formula C(n) = ∑C(k)C(n-k-1) is a recurrence relation for Catalan numbers.
- True
- False
💡 Hint: Recall the formation of the recurrence.
Solve and get performance evaluation
Challenge Problems
Push your limits with challenges.
Question 1
Create and describe a new problem related to valid parenthesis without violating the matching condition.
💡 Hint: Think about restrictions on placement.
Question 2
Propose an algorithm to count valid strings of n parenthesis using dynamic programming.
💡 Hint: Look into how states can be represented.
Challenge and get performance evaluation