Graph search function GRAPH-SEARCH(problem,fringe)returns a solution, or failure closed an empty set fringe-INSERT(MAKE-NODE(INITIAL- STATE problem),fringe) loop do if fringe is empty then return failure node REMOVE-FRONT(fringe) if GOAL-TEST(problem,STATE[nodel)then return node if STATE[node is not in closed then add STATE[node to closed fringe -INSERTALL(EXPAND(node,problem),fringe) end 口卡回t·三4色，是分Q0. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Graph search