program sample
implicit none
integer A,B,C,D
write(*,*)A,B,C,D
1 C=C-B
If (C<0) then
   WRITE(*,*) "YES"
   GOTO 2
END IF
A=A-D
IF If (A<0) then
   WRITE(*,*) "NO"
   GOTO 2
ELSE 
GO TO 1
END IF
2
stop
end program sample

