Iterative Refinement, cont.
/* There are n2 rooms arranged in an n-by-n grid. Some adjacent rooms have connecting doors. No doors lead outside. You are in the upper-leftmost room facing left. A sequence of doors leads to the lower-rightmost room. Get there. */
while ( you are not in lower rightmost room )
/* Get “closer” to lower rightmost room. */
Different notions of “closer” lead to different versions of
/* Get “closer” to lower rightmost room. */
Notion A: wall length away, using the “lefthand rule”.
Notion B: # of rooms away, using the “lefthand rule”.