PROGRAM LABELS(INPUT,OUTPUT);                               
  LABEL 1,2;                                                
  VAR J: INTEGER;                                           
                                                            
  PROCEDURE P;                                              
  LABEL 3,4;                                                
  VAR I: INTEGER;                                           
  BEGIN                                                     
    GOTO 3;                                                 
    FOR I:=1 TO 3 DO                                        
      BEGIN                                                 
        3: WRITELN(I);                                      
        GOTO 4                                              
      END;                                                  
    4: GOTO 1;                                              
   END; (* P *)                                             
                                                            
BEGIN                                                       
  GOTO 3;                                                   
  FOR J:= 5 DOWNTO 0 DO                                     
    BEGIN                                                   
      2: WRITELN(J);                                        
      IF J=0 THEN GOTO 1;                                   
      WRITELN(1/J);                                         
      1: WRITELN; P                                         
    END;                                                    
  GOTO 2;                                                   
END.