C++ Tutorial/Operators statements/complement

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Demonstrate bitwise complement

#include <iostream>
using std::cout;
#include <iomanip>
using std::endl;
using std::setw;
void displayBits( unsigned );
int main()
{
   unsigned number1;
   unsigned number2;
   unsigned mask;
   unsigned setBits;
   number1 = 21845;
   cout << "\nThe one"s complement of\n";
   displayBits( number1 );
   cout << "is" << endl;
   displayBits( ~number1 );

   return 0;
}
//Quote from
//C++ How to Program (5th Edition) (How to Program) (Paperback)
//by Harvey & Paul) Deitel & Associates
//Publisher: Prentice Hall; 5 edition (January 5, 2005)
//Language: English
//ISBN-10: 0131857576
//ISBN-13: 978-0131857575
void displayBits( unsigned value ) {
   const int SHIFT = 8 * sizeof( unsigned ) - 1;
   const unsigned MASK = 1 << SHIFT;
   cout << setw( 10 ) << value << " = ";
   for ( unsigned i = 1; i <= SHIFT + 1; i++ ) {
      cout << ( value & MASK ? "1" : "0" );
      value <<= 1;
      if ( i  8 == 0 )
         cout << " ";
   }
   cout << endl;
}
The one"s complement of
     21845 = 00000000 00000000 01010101 01010101
is
4294945450 = 11111111 11111111 10101010 10101010

The complement of the number

#include <iostream>
using namespace std;
void show_binary(unsigned int u);
int main()
{
  unsigned u = 123;

  cout << "Here"s the number in binary: ";
  show_binary(u);
  cout << "Here"s the complement of the number: ";
  show_binary(~u);
  return 0;
}
void show_binary(unsigned int u)
{
  int t;
  for(t=128; t>0; t = t/2)
    if(u & t) cout << "1 ";
    else cout << "0 ";
  cout << "\n";
}
Here"s the number in binary: 0 1 1 1 1 0 1 1
Here"s the complement of the number: 1 0 0 0 0 1 0 0