Function FileExists (Name : String) : boolean;
Var F : File;
begin
{$i-}
Assign (F,Name);
Reset (F);
{$I+}
FileExists:=(IoResult=0) and (Name<>'');
Close (f);
end; { FileExists }
procedure parse_fichier(f : string);
var
ft : text;
st : string;
s1,s2 : string;
i,j : integer;
c : char;
a : arbre;
begin
if not(FileExists(f)) then
begin
writeln('le fichier ', f, ' n''existe pas');
exit;
end;
assign(ft,f);
reset(ft);
a := creer_arbre_vide();
while not(eof(ft)) do
begin
readln(ft,st);
s1 := copy(st,1,pos(' ',st)-1);
s2 := copy(st,pos(' ',st)+1,length(st)-pos(st,' '));
val(s1,i);
val(s2,j);
writeln('>>',i,' ',j);
inserer_point(creer_point(i,j),a);
end;
end; { parse_fichier }