/*Solve depth bounded interpreter example on page 64.*/
 
:- [dsutil,pdsdb,pdsdc,pdsini].
 
isort([X|Xs],Ys) :- isort(Xs,Zs),insert(X,Zs,Ys).
isort([],[]).
 
insert(X,[Y|Ys],[X,Y|Ys]) :- X =< Y.
insert(X,[Y|Ys],Zs) :- insert(X,Ys,Ws),insert(Y,Ws,Zs).
insert(X,[],[X]).
