Recursion

一、Recursion

1,A predicate is recursively defined if one or more rules in its definition refers to itself 2,example \(1\) \(2\) \(3\) \(4\) \(5\) （6）

child(anna,bridget). child(bridget,caroline). child(caroline,donna). child(donna,emily). descend(X,Y):- child(X,Y). descend(X,Y):- descend(Z,Y), child(X,Z). ？-descend(A,B).

二、Prolog and Logic

1,Prolog was the first reasonable attempt to create a logic programming language 2,特点 not have to tell the computer what to do To get information, simply asks a query Prolog is not a full logic programming language!