C NULLS.F - FOR REMOVING NULLS FROM LDT
      CHARACTER*24 FRONT
      CHARACTER* 32 BACK
      INTEGER*4 EAST,NORTH
      OPEN(UNIT=3,FILE='bass55.ldt',READONLY)
      OPEN(UNIT=4,FILE='bass55.dat')
   10 READ(3,100,END=20) FRONT,EAST,NORTH,BACK
      IF (EAST .EQ. 0 .OR. NORTH .EQ. 0) GOTO 10
C SKIP BLANKS
      WRITE(4,100) FRONT,EAST,NORTH,BACK
  100 FORMAT(A24,I8,I8,A32)
      GOTO 10
C
   20 CONTINUE
      STOP
      END