Useful Links
C Tutorial : http://www.cprogramming.com/tutorial/c-tutorial.html
C plusplus : http://www.cplusplus.com/
Online compiler : http://codepad.org/
C++ online test : http://www.tutorialspoint.com/cplusplus/cpp_online_test.htm
C++ quiz : http://www.mycppquiz.com/
C 언어기초 오픈강의 : http://www.kocw.net/home/search/kemView.do?kemId=670267
C 프로그래밍 강좌 : http://dblab.duksung.ac.kr/ds/course1.html
C language tutorial : http://www.physics.drexel.edu/courses/Comp_Phys/General/C_basics/c_tutorial.html
How to start : https://youtu.be/X60GgBorqbE
행렬 관련 강좌 1 : https://www.youtube.com/watch?v=QCJd8R8G1lk
행렬 관련 강좌 2 : https://www.youtube.com/watch?v=m4quGRilsAY
행렬 관련 강좌 3 : https://www.youtube.com/watch?v=qwEWO-cQwXQ
행렬 관련 정보 : http://poovp.tistory.com/11
행렬 관련 정보 : http://gcland.tistory.com/130
행렬 관련 정보 : http://elwlsek.tistory.com/216
scanf()와 scanf_s() 차이 1: http://tip.daum.net/question/54246283
scanf()와 scanf_s() 차이 2: http://blog.naver.com/PostView.nhn?blogId=jkssleeky&logNo=220611708111
scanf()와 scanf_s() 차이 3: http://sks3297.tistory.com/entry/C%EC%96%B8%EC%96%B4-scanf%EC%99%80-scanfs%EC%9D%98-%EC%B0%A8%EC%9D%B4
scanf()와 scanf_s() 차이 4: http://jhepark.tistory.com/15
scanf()와 scanf_s() 차이 5: https://www.clien.net/service/board/kin/7925672
scanf() error: http://bymakers.tistory.com/m/6
scanf, scanf_s error 수정법: https://bymakers.tistory.com/6
Online debugging website: https://www.onlinegdb.com/