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std::setw(3)		      C++ Standard Libary		  std::setw(3)

NAME
       std::setw - std::setw

Synopsis
	  Defined in header <iomanip>
	  /*unspecified*/ setw(	int n );

	  When used in an expression out << setw(n) or in >> setw(n), sets the
       width parameter
	  of the stream	out or in to exactly n.

Parameters
	  n - new value	for width

Return value
	  Returns  an  object of unspecified type such that if str is the name
       of an output
	  stream  of  type  std::basic_ostream<CharT,  Traits>	 or   std::ba-
       sic_istream<CharT,
	  Traits>,  then  the  expression str << setw(n) or str	>> setw(n) be-
       haves as	if the
	  following code was executed:

	  str.width(n);

Notes
	  The width property of	the stream will	be reset to zero (meaning "un-
       specified") if
	  any of the following functions are called:

	    * Input

		     * operator>>(basic_istream&, basic_string&)
		     * operator>>(basic_istream&, char*)

	    * Output

		     * Overloads 1-7 of	basic_ostream::operator<<() (at	 Stage
       3 of
		       num_put::put())
		     *	operator<<(basic_ostream&,  char)  and	operator<<(ba-
       sic_ostream&, char*)
		     * operator<<(basic_ostream&, basic_string&)
		     * std::put_money (inside money_put::put())
		     * std::quoted (when used with an output stream)

	  The exact effects this modifier has on the input and output vary be-
       tween the
	  individual I/O functions and are described at	 each  operator<<  and
       operator>>
	  overload page	individually.

Example
       // Run this code

	#include <sstream>
	#include <iostream>
	#include <iomanip>

	int main()
	{
	    std::cout << "no setw: [" << 42 << "]\n"
		      << "setw(6): [" << std::setw(6) << 42 << "]\n"
		      <<  "setw(6), several elements: [" << 89 << std::setw(6)
       << 12 <<	34 << "]\n";
	    std::istringstream is("hello, world");
	    char arr[10];
	    is >> std::setw(6) >> arr;
	    std::cout << "Input	from \"" << is.str() <<	"\" with setw(6)  gave
       \""
		      << arr <<	"\"\n";
	}

Output:
	no setw: [42]
	setw(6): [    42]
	setw(6), several elements: [89	  1234]
	Input from "hello, world" with setw(6) gave "hello"

See also
	  width	     manages field width
		     (public member function of	std::ios_base)
	  setfill    changes the fill character
		     (function template)
	  internal   sets the placement	of fill	characters
	  left	     (function)
	  right
	  showbase   controls whether prefix is	used to	indicate numeric base
	  noshowbase (function)

http://cppreference.com		  2022.07.31			  std::setw(3)

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