Bitwise operator: ^
#include <iostream>
#include <iomanip>
using std::cout;
using std::endl;
using std::setfill;
using std::setw;
int main() {
unsigned long red = 0XFF0000UL; // Color red
unsigned long white = 0XFFFFFFUL; // Color white - RGB all maximum
cout << std::hex; // Set hexadecimal output format
cout << setfill("0"); // Set fill character for output
unsigned long mask = red ^ white;
cout << "\n mask = red white = " << setw(8) << mask;
cout << "\n mask red = " << setw(8) << (mask ^ red);
cout << "\n mask white = " << setw(8) << (mask ^ white);
return 0;
}mask = red ^ white = 0000ffff
mask ^ red = 00ffffff
mask ^ white = 00ff0000
Bitwise operators: Complement, AND, OR
#include <iostream>
#include <iomanip>
using std::cout;
using std::endl;
using std::setfill;
using std::setw;
int main() {
unsigned long red = 0XFF0000UL; // Color red
unsigned long white = 0XFFFFFFUL; // Color white - RGB all maximum
cout << std::hex; // Set hexadecimal output format
cout << setfill("0"); // Set fill character for output
cout << "\nTry out bitwise AND and OR operators.";
cout << "\nInitial value red = " << setw(8) << red;
cout << "\nComplement ~red = " << setw(8) << ~red;
cout << "\nInitial value white = " << setw(8) << white;
cout << "\nComplement ~white = " << setw(8) << ~white;
cout << "\n Bitwise AND red & white = " << setw(8) << (red & white);
cout << "\n Bitwise OR red | white = " << setw(8) << (red | white);
return 0;
}Try out bitwise AND and OR operators.
Initial value red = 00ff0000
Complement ~red = ff00ffff
Initial value white = 00ffffff
Complement ~white = ff000000
Bitwise AND red & white = 00ff0000
Bitwise OR red | white = 00ffffff
Display the bits within a byte.
#include <iostream>
using namespace std;
void show_binary(unsigned int u);
int main()
{
show_binary(89);
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";
}0 1 0 1 1 0 0 1
Printing an unsigned integer in bits
#include <iostream>
using std::cout;
using std::cin;
using std::endl;
#include <iomanip>
using std::setw;
int main()
{
unsigned value = 123;
const int SHIFT = 8 * sizeof( unsigned ) - 1;
const unsigned MASK = 1 << SHIFT;
for ( int i = 1; i <= SHIFT + 1; i++ )
{
cout << ( value & MASK ? "1" : "0" );
value <<= 1;
if ( i % 8 == 0 )
cout << " ";
}
cout << endl;
return 0;
}00000000 00000000 00000000 01111011
Use masks to select or set a particular flag bit
#include <iostream>
#include <iomanip>
using std::cout;
using std::endl;
using std::setfill;
using std::setw;
int main() {
unsigned long flags = 0xFF; // Flags variable
unsigned long bit1mask = 0x1; // Selects bit 1
unsigned long bit6mask = 0x20; // Selects bit 6
unsigned long bit20mask = 0x80000; // Selects bit 20
cout << "\nSelect bit 1 from flags : " << setw(8) << (flags & bit1mask);
cout << "\nSelect bit 6 from flags : " << setw(8) << (flags & bit6mask);
cout << "\nSwitch off bit 6 in flags : " << setw(8) << (flags &= ~bit6mask);
cout << "\nSwitch on bit 20 in flags : " << setw(8) << (flags |= bit20mask);
cout << endl;
return 0;
}Select bit 1 from flags : 1
Select bit 6 from flags : 32
Switch off bit 6 in flags : 223
Switch on bit 20 in flags : 524511
