US Meta E4/E5 - E4 Pass

Phone Screen : Question 1: Convert Binary Search Tree to Sorted Doubly Linked List Question 2: Accounts Merge

Onsite Loop : Coding Round 1 : Question 1: Continuous Subarray Sum Question 2: Sparse multiplication of a matrix. Provided just the row and cols and values of the 2 matrices containing non-zero elements.

Coding Round 2: Question 1 : Candy crush. Similar to Remove All Adjacent Duplicates In String, but without a limitation on count. Burst similar characters. Input: "aaabbbc" Output: "c" Explanation:

1. Remove 3 'a': "aaabbbbc" => "bbbbc"
2. Remove 4 'b': "bbbbc" => "c" Question 2 : Lowest Common Ancestor of a Binary Tree II

Coding Round 3 : Question 1: Clone Graph Question 2: Top K Frequent Elements For question 1, a DFS approach was used. For Question 2, three approaches were discussed: Priority Queue, Quick Sort and Count sort. Count sort was implemented.

Behavioral Round: Standard behavioral questions:

1. Critical feedback from manager
2. Most complicated project
3. Conflict with a teammate
4. Tight deadline

System Design : Online Coding Judge: Multiple competitions running concurrently, generating scores for each user, and displaying a real-time ranking board.

An additional coding round was required due to a delay in feedback submission for a previous round. Passed for E4. E5 was not offered due to limited previous work scope not aligning with E5 requirements.