Heuristics: A*-algorithm 2

Example: Imagine a navigation device, just simpler: You have a two-dimensional grid (internal represented by a graph were every box is connected if there is no obstacle inbetween) and want to know the shortest path between A (start) and B (target). Cost for moving horicontally and vertically in this example are 10 and moving diagonal costs 14 (Pythagorean theorem). Between the start node and the target node are some obstacles placed (dark box). As a heuristic the airline will be used.