Hello!

Are you sure your algorithm is OK? Consider world2:

########################

#f.D.E.e.C.b.A.@.a.B.c.#

######################.#

#d.....................#

#######################

Hero goes

1) left til the end = "f.D.E.e.C.b.A."

2) right till the end = ".D.E.e.C.b.A.@.a.B.c."

3) down 1 step = "."

4) left to the end = d....................."

sum of lengths = 58; not 86