Obstacles on the Map

An obstacle is any square you may not enter. On the map it might look like a rock, a tree, or a dark wall tile. Your path must use only open squares.

When you trace a route, slide your finger around the obstacle like water flowing past a stone. If your finger would cross a dark square, pick a new lane.

Load an obstacle course in the robot lab. A plan that worked on an empty grid might now bump on square three. The wall was always there; the plan ignored it.

Sometimes the shortest line crosses a wall. The legal path bends. Add turns to skirt the edge of the obstacle even if the map looks longer.

If two ways around exist, compare step counts again. One side might need only one extra turn while the other needs three forwards.

When the robot bumps, mark the square on your paper map. That is the step where your path tried to cross a blocker.

Parks, museums, and schools all have obstacles: fences, ponds, closed doors. Maps show them so you do not waste steps walking into a dead end.

Games use the same trick. Mazes are grids with many obstacles. The skill is reading and revising, not memorising one lucky path.

Next you will focus on turns that aim the robot before it moves forward.