Advent of Code 2025

solutions in J

Day 1

NB. part 1
+/0=100|+/\*/"_1(1 50),(1&-@('R-L'&i.@{.),".@}.)@>"_1<;._2 input

NB. part 2
+/+/(0=100&|@([+*@-~*>:@i.@-~)/)"_1(2 1$1 2),;._3+/\*/"_1(1 50),(1&-@('R-L'&i.@{.),".@}.)@>"_1<;._2 input