E4 地点 MPK

我有4年工作经验，目前是 SDE 1

面的是 Generalist E4

**Onsite**

**第一轮 (Coding)** :

- determine if the given string is a valid integer.

This is very similar to AtoI but an easier version - https://leetcode.com/problems/string-to-integer-atoi/ - What is the complexity of finding the max value of an element in an array

Big O, Big Theta, Big Omega

**第二轮 (系统设计)** :

Design a live reload feature for Instagram comments (new comments appear instantly)

午饭

**第三轮 (Coding)** :

- Given an array find if it is monotonically increasing or not

https://leetcode.com/problems/monotonic-array/ - Find the contiguous subarray sum equal to K

https://leetcode.com/problems/continuous-subarray-sum/ however negatives were allowed in the input

**第四轮 (Behavioral)** :

- Behavioral questions like greatest technical challenge, interpersonal challenge, etc
- Given an array of words, find which pairs of words form palidromes

**第五轮 (coding)** :

- Find a binary tree’s boundary(perimeter) nodes

https://leetcode.com/problems/boundary-of-binary-tree/ - Count the number of islands in a 2D array (diagonal movements allowed)

https://leetcode.com/problems/number-of-islands/ , went into indepth discussion of iterative vs recursive solution, and optimizing recursive calls (bounds checking before recursing)

**第六轮 (coding)** :

- Add two numbers

https://leetcode.com/problems/add-two-numbers/ the digits were stored in a list and in non-reverse order. Could be negative numbers ex ["-",“1”,“3”] - Subtract two numbers

Same as above but subtracting the two numbers instead of adding