i:.''0:"i/10.in"
c:,/-:\=2                   / (right;down;left;up)
a:{(y=i./:)#'(,/c+\:/:)'x}  / advance[trails;targetHeight]
s:(,'+&~i)a/1+!9            / finish points of each trailhead
#,/?'s                      / part 1: number of unique finish points for each trailhead
#,/s                        / part 2: total number of finish points

Another fun and easy day!

~/aoc24k/10.html