added more links to information security (#3961)

* Update problem-sets-competitive-programming.md

* Update problem-sets-competitive-programming.md

* Update problem-sets-competitive-programming.md

* alphabetize

Co-authored-by: Eric Hellman <eric@hellman.net>

problem-sets-competitive-programming.md

@@ -62,6 +62,8 @@
 
 * [ångstromCTF](https://angstromctf.com)
 * [CTFtime](https://ctftime.org)
+* [Hacker101](https://ctf.hacker101.com)
+* [InCTF](https://inctf.in)
 
 
 ### Problem Sets