PROGRAM ORDER(INPUT,OUTPUT);                                
TYPE PTR=^NODE;                                             
     NODE= RECORD                                           
            INFO:CHAR;                                      
            LLINK,RLINK:PTR                                 
           END;                                             
VAR ROOT:PTR;CH:CHAR;                                       
                                                            
PROCEDURE ENTER(VAR P:PTR);                                 
BEGIN                                                       
 READ(CH);                                                  
 IF CH<>"." THEN                                            
  BEGIN NEW(P);                                             
   P^.INFO:=CH;                                             
   ENTER(P^.LLINK);                                         
   ENTER(P^.RLINK);                                         
  END                                                       
 ELSE P:=NIL                                                
END;(*ENTER*)                                               
                                                            
PROCEDURE POSTORDER(P:PTR);                                 
 LABEL 1,3;                                                 
VAR S:ARRAY[0..20]OF PTR;                                   
    SP:INTEGER;                                             
                                                            
BEGIN                                                       
 SP:=0;                                                     
 1:S[SP]:=P;SP:=SP+1;                                       
   IF P^.LLINK<>NIL THEN                                    
   BEGIN P:=P^.LLINK;GOTO 1 END;                            
 3:SP:=SP-1;P:=S[SP];                                       
   IF P^.RLINK<>NIL THEN                                    
   BEGIN P:=P^.RLINK;GOTO 1 END;                            
   WRITE(P^.INFO);IF SP<>0 THEN GOTO 3;                     
END;                                                        
                                                            
PROCEDURE POST(P:PTR);                                      
BEGIN                                                       
 IF P<>NIL THEN                                             
  BEGIN POST(P^.LLINK);                                     
        POST(P^.RLINK);                                     
        WRITE(P^.INFO);                                     
  END                                                       
END;                                                        
                                                            
BEGIN                                                       
 ENTER(ROOT);READLN;WRITELN;                                
 POSTORDER(ROOT);WRITELN                                    
 POST(ROOT);WRITELN                                         
END.