--- pl:prolog:pllib:graph_path [2019/06/27 15:50]
+++ pl:prolog:pllib:graph_path [2019/06/27 15:50] (aktualna)
@@ Linia 1: / Linia 1: @@
+====== Graph path ======
+{{tag>graphs}}
+===== Description =====
+Finding a path by depth-first search.
+**Source**:  The Art of Prolog
+===== Download =====
+Program source code: {{graph_path.pl}}
+===== Listing =====
+<code prolog>
+/*
+	connected(X,Y) :-
+		Node X is connected to node Y,
+		given an edge/2 relation describing a DAG.
+*/
+     connected(X,X).
+     connected(X,Y) :- edge(X,N), connected(N,Y).
+  /*  Data   */
+     edge(a,b).
+     edge(a,c).
+     edge(a,d).
+     edge(a,e).
+     edge(d,j).
+     edge(c,f).
+     edge(c,g).
+     edge(f,h).
+     edge(e,k).
+     edge(f,i).
+     edge(x,y).
+     edge(y,z).
+     edge(z,x).
+     edge(y,u).
+     edge(z,v).
+/*  path(X,Y,Path) :-
+		Path is a path between two nodes X and Y in the
+		DAG defined by the relation edge/2
+*/
+     path(X,X,[X]).
+     path(X,Y,[X|P]) :- edge(X,N), path(N,Y,P).
+%	Program 14.9: Finding a path by depth-first search
+</code>
+===== Comments =====

pl/prolog/pllib/graph_path.txt · ostatnio zmienione: 2019/06/27 15:50 (edycja zewnętrzna)

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