- What is a module?
- What is the difference between include and extends?
- What does self.inlcuded(base) do?
- What is a blockchain?
- How does a transaction get registered to the blockchain?
- Reach out to 2 people
- Apply to 5 jobs
Welcome to the end of Week 8! The next step is to double down on what you've learned, and prepare for the HackerRank test that will be sent to your email address. The first step is to work through this practice test to have an idea of what to expect on the HackerRank exam.
Before you dive into the HackerRank test, it's important to review. We use the HackerRank test results to gauge your progress in the job search guide, so you'll want to make sure you are as prepared as possible. If you struggle on this practice exam, be sure to review flash cards!
Make an honest effort with these problems. An answer key is at the bottom of the page, but try and review your notes and readings before referring to these.
- Choose the correct statement(s) about designing a Messaging Service or Uber
- A) When you design a message service with multiple application servers, you don't need a database for unread messages because these messages can be expected to live in server memory
- B) Service Oriented architecture refers to having dedicated servers to serve web pages to customers.
- C) Provisioning an SOA is often done with dockerized environments that contain all the system dependencies
- D) Canary testing refers to allowing a small amount of production traffic onto a system that is being tested
- Choose the correct statements about Dynamic Programming problems
- A) Longest Common Subsequence and Edit Distance both rely on overlapping subproblems that call for the minimum solution of the next shortest string
- B) Longest Increasing Subsequence is solved by generating all the longest subsequences that terminate with each item in the input
- C) Longest Increasing Subsequence and Edit Distance both memoize using a 2D matrix
- D) Minimum Partition Sum Difference problem requires trying to generate all possible sums up to the sum of the entire set in a matrix
- Choose the correct statement(s) about Ruby
- A) Ruby is always pass by reference
- B) When you point two variables at an object and then alter the object, both variables will reference the changed object
- C) Modules must contain instance methods
- D) You can use a method to include class methods from a module in your class without using the
extendskeywords - E) The shovel operator on arrays mutates the original array
- F)
.concatreturns a new array - G)
+=on a String returns a new object
- C, D
- B, D
- B, D, E