LeetCode Basics
How many LeetCode problems typically appear in a technical interview?
1-3
What is the first step of the UMPIRE method?
Understand
What does Big O notation describe?
How the runtime of code scales with input size
Are arrays ordered or unordered?
Ordered
Can a set contain duplicate values?
No
What is LeetCode mainly used for?
Practicing coding problems for technical interviews
What is the "P" in UMPIRE?
Plan
What is the Big O of printing a single statement?
O(1)
How do you access elements in an array?
By their index/number
Are sets ordered or unordered?
Unordered
What is a technical interview assessing?
Technical knowledge, especially data structures and algorithms
What is the number one question we should ask during the Plan step of UMPIRE?
What is the problem we are trying to solve?
What is the Big O of a loop inside of another loop?
O(N^2)
What data structure is like a notebook with words and meanings?
Hash Map/Dictionary
Is a stack First In First Out (FIFO) or Last In First Out (LIFO)?
First In First Out (FIFO)
True or False: LeetCode problems always have clearly defined goals?
True
What should you create in the "Plan" step?
Visualizations and pseudocode
In Big O, are we concerned with exact runtime or the trend?
The trend
Which is faster for looking up a value: searching an array or using a hash map (on average)?
Hash map
How do you know you've reached the end of linked list?
You reach a NULL value
Besides specific problems which a clear goal and example input and outputs, what is the last vital part of a leetcode problem?
Constraints
In UMPIRE, what should you use to understand the interviewer's question?
Test cases and questions about the problem
If a code's runtime increases directly with the input size, what's its Big O?
O(n)
What data structure will you use most frequently when doing leetcode?
Hashmaps!!!
What are sets really good for?
Checking membership