Overview

This is my Python Leetcode solution. As time grows, this also become a guide to prepare for software engineer interview.
The solution is at problems/python/ or problems/python3/. For example, merge-sorted-array.py's solution is at https://leetcode.com/problems/python/merge-sorted-array/.
I really take time tried to make the best solution and collect the best resource that I found.
Because I wanted to help others like me.
Please BUY ME A COFFEE if you want to show support.

Leetcode Problem Lists

I found it makes sense to solve similar problems together, so that we can recognize the problem faster when we encounter a new one. My suggestion is to skip the HARD problems when you first go through these list.

https://neetcode.io/practice (150 problems with video explaination)
https://www.programcreek.com/2013/08/leetcode-problem-classification/
https://github.com/wisdompeak/LeetCode
https://docs.google.com/spreadsheets/d/1SbpY-04Cz8EWw3A_LBUmDEXKUMO31DBjfeMoA0dlfIA/edit#gid=126913158 (huahua).
https://leetcode.com/list/?selectedList=535ukjh5 (Only 74 problems)

Software Engineer Interview

Overall Mindset

Having a right mindset is the most important one. It keeps you going when you are tired after work. Studying when everyone else are out having fun. Reminding you that your goals are not going to come easy, it takes time, self-discipline, mental and physical toughness...
How to Get a Job at the Big 4.
How I Got a Job at Google as a Software Engineer.
The #1 Daily Habit of Those Who Dominate with Andy Frisella. It is also avaliable on Spotify or Youtube, just google it.

Prepare in a Structural Way

Data Structures and Algorithms for beginners

If you are new or know nothing about data structures and algorithms, I recommend this course. This course is taught in Python and design to help you find job and do well in the interview.

System Design

More resource
Architecture 101
Systems Design Interview Concepts. There are also lots of tech interview related topic in his channel.
Narendra's Youtube Channel
System Design Primer

Knowledge Base Question

Session vs Cookie
Token Authentication
TCP/UDP
- Transport Layer
  - Application Layer (HTTP, FTP)
  - Transport Layer (UDP/TCP, Slice data to small packages)
  - Network Layer (IP)
  - Link Layer (Wifi)
  - Physical Layer (Coaxial Ethernet Cable)
- UDP has smaller package size (8 bytes), while TCP needs 20 bytes due to it has larger header.
- UDP are not order guaranteed. TCP are in order.
- They both have error messages, but TCP will resent it again, UDP does not.
- TCP needs a three-way handshake to initiate a connection between ports. It’s like a phone call. While UDP is like a mail.
- In short, UDP is smaller and faster while TCP is reliable and ordered.
- UDP example, video streaming, DNS lookups.
HTTPS, CA, PKI
HTTP, HTTP Code, Socket, WebSocket, HTTP KeepAlive, HTTP2
DNS, CNAME, NS, A, AAAA, IPv4, IPv6
Code, Process, Thread
Stack memory vs Heap memory
- Stack memory
  - Stores temporary variable created by functions.
  - Memory is managed by CPU for you. No need to allocate and free it by hand.
  - L.I.F.O.
  - Stacks has limit (That is why we seldom use recursion real life)
  - Stacks variable are local variable in nature.
- Heap memory
  - Larger.
  - Slightly slower. Because we has to use "pointers" to access.
  - We are responsible to free() the memory.
  - Heap variable is global variable in nature.
GET vs POST
CORS
...