Advent of Code 2021 solutions:

Day	Title	C#
1	Sonar Sweep	⭐ ⭐
2	Dive!	⭐ ⭐
3	Binary Diagnostic	⭐ ⭐
4	Giant Squid	⭐ ⭐
5	Hydrothermal Venture	⭐ ⭐
6	Lanternfish	⭐ ⭐
7	The Treachery of Whales	⭐ ⭐
8	Seven Segment Search	⭐ ⭐
9	Smoke Basin	⭐ ⭐
10	Syntax Scoring	⭐ ⭐
11	Dumbo Octopus	⭐ ⭐
12	Passage Pathing	⭐ ⭐
13	Transparent Origami
14	Unknown
15	Unknown
16	Unknown
17	Unknown
18	Unknown
19	Unknown
20	Unknown
21	Unknown
22	Unknown
23	Unknown
24	Unknown
25	Unknown