Basic C:
Miss undertanding in C
https://zh.m.wikibooks.org/zh-tw/C_%E8%AA%9E%E8%A8%80%E5%B8%B8%E8%A6%8B%E8%AA%A4%E8%A7%A3
Good References:
https://github.com/grandyang/leetcode
https://www.youtube.com/channel/UC5xDNEcvb1vgw3lE21Ack2Q
Online Complier:
https://www.onlinegdb.com/online_c++_compiler
https://www.tutorialspoint.com/compile_cpp_online.php
STL references:
https://mropengate.blogspot.com/2015/07/cc-vector-stl.html
https://mropengate.blogspot.com/2015/12/cc-map-stl.html
GeekforGeeks
https://www.geeksforgeeks.org/multiset-in-cpp-stl/
https://www.geeksforgeeks.org/greedy-algorithms/
System Design
https://github.com/donnemartin/system-design-primer
https://www.youtube.com/channel/UC9vLsnF6QPYuH51njmIooCQ