Advent of Code solutions

gitignore update

+1
+1
.gitignore
··· 6 build 7 *.hi 8 *.o 9 p1 10 !p1/ 11 .p1
··· 6 build 7 *.hi 8 *.o 9 + *.ll 10 p1 11 !p1/ 12 .p1