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      std::boolalpha,std::noboolalpha

      From cppreference.com
      <cpp‎ |io‎ |manip
       
       
       
      Input/output manipulators
      Floating-point formatting
      Integer formatting
      Boolean formatting
      boolalphanoboolalpha
      Field width and fill control
      Other formatting
      Whitespace processing
      Output flushing
      Status flags manipulation
      Time and money I/O
      (C++11)
      (C++11)
      (C++11)
      (C++11)
      Quoted manipulator
      (C++14)
       
      Defined in header<ios>
      std::ios_base& boolalpha(std::ios_base& str);
      (1)
      std::ios_base& noboolalpha(std::ios_base& str);
      (2)
      1) Enables theboolalpha flag in the streamstr as if by callingstr.setf(std::ios_base::boolalpha).
      2) Disables theboolalpha flag in the streamstr as if by callingstr.unsetf(std::ios_base::boolalpha).

      std::boolalpha is an I/O manipulator, so it may be called with an expression such asout<< std::boolalpha for anyout of typestd::basic_ostream or with an expression such asin>> std::boolalpha for anyin of typestd::basic_istream.

      Contents

      [edit]Parameters

      str - reference to I/O stream

      [edit]Return value

      str (reference to the stream after manipulation).

      [edit]Example

      Run this code
      #include <iostream>#include <sstream> int main(){// boolalpha outputstd::cout<<"default true: "<<true<<'\n'<<"default false: "<<false<<'\n'<< std::boolalpha<<"boolalpha true: "<<true<<'\n'<<"boolalpha false: "<<false<<'\n'<< std::noboolalpha<<"noboolalpha true: "<<true<<'\n'<<"noboolalpha false: "<<false<<'\n'; // boolalpha parsebool b1, b2;std::istringstream is("true false");    is>> std::boolalpha>> b1>> b2; std::cout<<'"'<< is.str()<<"\" parsed as: "<< std::boolalpha<< b1<<' '<< b2<<'\n';}

      Output:

      default true: 1default false: 0boolalpha true: trueboolalpha false: falsenoboolalpha true: 1noboolalpha false: 0"true false" parsed as: true false

      [edit]See also

      clears the specified ios_base flags
      (function)[edit]
      sets the specifiedios_base flags
      (function)[edit]
      provides the string to use as the name of the booleantrue andfalse
      (virtual protected member function ofstd::numpunct<CharT>)[edit]
      Retrieved from "https://en.cppreference.com/mwiki/index.php?title=cpp/io/manip/boolalpha&oldid=159200"

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