Type for format flags.
  Bitmask type to store format flags. The flag values can be any combination of the following constant member values:

flag	effect if set
ios_base::boolalpha	input/output bool objects as alphabetic names (true, false).
ios_base::dec	input/output integer in decimal base format.
ios_base::fixed	output floating point values in fixed-point notation.
ios_base::hex	input/output integer in hexadecimal base format.
ios_base::internal	the output is filled at an internal point enlarging the output up to the field width.
ios_base::left	the output is filled at the end enlarging the output up to the field width.
ios_base::oct	input/output integer in octal base format.
ios_base::right	the output is filled at the beginning enlarging the output up to the field width.
ios_base::scientific	output floating-point values in scientific notation.
ios_base::showbase	output integer values preceded by the numeric base.
ios_base::showpoint	output floating-point values including always the decimal point.
ios_base::showpos	output non-negative numeric preceded by a plus sign (+).
ios_base::skipws	skip leading whitespaces on certain input operations.
ios_base::unitbuf	flush output after each inserting operation.
ios_base::uppercase	output uppercase letters replacing certain lowercase letters.

constant	value
ios_base::adjustfield	left | right | internal
ios_base::basefield	dec | oct | hex
ios_base::floatfield	scientific | fixed

See also.
  flags, setf, unsetf
  manipulators boolalpha, dec, fixed, hex, internal, left, noboolalpha, noshowbase, noshowpoint, noshowpos, noskipws, nounitbuf, nouppercase, oct, right, scientific, showbase, showpoint, showpos, skipws, unitbuf and uppercase
  ios_base class