Putting More Detail into Nodes

Now we have the mechanism, we can let nodes carry further information, e.g.

• Node Depth: (depth limited search; iterative deepening strategy).
• G-cost (path cost - for uniform cost search).
• H-cost (heuristic cost - for greedy search)
• F-cost (= f(H,G) - for A* and other search strategies)

% node data structure

node_state_of(  n(X,_,_,_),  X).
node_parent_of( n(_,X,_,_),  X).
node_depth_of(  n(_,_,X,_),  X).
node_gcost_of(  n(_,_,_,X),  X).

% make node

node_new(n(_,_,_,_)).