My solution to the picobot problem at https://www.cs.hmc.edu/picobot/

scan2darray

# State zero, move north if nothing to north else move west
0 x*** -> N 0
0 N*** -> X 1

# Move west state
#  If nothing to the west move West
#  If end of row move south then east
#  If at top left corner move East
#  If at bottom left corner do nothing
1 **x* -> W 1
1 x*Wx -> S 2
1 NxWx -> X 2
1 xxWS -> X 1

# Move east state
#  If nothing on the East move east
#  If end of row move south then west
#  If bottom right corner do nothing
2 *x** -> E 2
2 *E*x -> S 1
2 *E*S -> X 2