Several member functions can be used to handle all the format definitions of a stream (see Table
15.10). The functions setf() and unsetf() set or clear, respectively, one or more flags. You
can manipulate multiple flags at once by combining them, using the “binary or” operator; that is,
operator |. The function setf() can take a mask as the second argument to clear all flags in a group
before setting the flags of the first argument, which are also limited to a group. This does not happen
with the version of setf() that takes only one argument. For example: