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==A bitset to hold 8-bits==

<source lang="cpp">#include <bitset>
#include <string>
#include <iostream>
int main ()
{
using namespace std;
// A bitset to hold 8-bits
bitset <8> eightBits;
cout << "Enter a 8-bit sequence: ";
// Store user-supplied sequence into the bitset
cin >> eightBits;
cout << endl;
return 0;
}</source>

==Create a copy of a bitset==

<source lang="cpp">#include <bitset>
#include <string>
#include <iostream>
int main ()
{
using namespace std;
// A bitset to hold 8-bits
bitset <8> eightBits;
cout << "Enter a 8-bit sequence: ";
// Store user-supplied sequence into the bitset
cin >> eightBits;
cout << endl;
// create a copy
bitset <8> flipInput (eightBits);
return 0;
}</source>

==Initialize a bitset with hex number==

<source lang="cpp">#include <bitset>
#include <iostream>
using namespace std;
int main( ){
const int num_lights = 15;
const bitset<num_lights> outside( 0xf );
const bitset<num_lights> inside( 0xff0 );
const bitset<num_lights> driveway( 0x7000 );
}</source>

==instantiate a bitset object for 8 bits, given an unsigned long init value==

<source lang="cpp">#include <bitset>
#include <iostream>
#include <string>
int main ()
{
using namespace std;
bitset <8> eightbits (255);
cout << "The initial contents of eightBits: " << eightbits << endl;
return 0;
}</source>

==Instantiate a bitset object for holding 4 bits, all initialized to "0000"==

<source lang="cpp">#include <bitset>
#include <iostream>
#include <string>
int main ()
{
using namespace std;
bitset <4> fourBits;
cout << fourBits << endl;
return 0;
}</source>

==Instantiate a bitset object for holding 5 bits, initialize it to a bit sequence supplied by a string==

<source lang="cpp">#include <bitset>
#include <iostream>
#include <string>
int main ()
{
using namespace std;
bitset <5> fiveBits (string ("10101"));
cout << fiveBits << endl;
return 0;
}</source>

==Read a binary number into a bitset==

<source lang="cpp">#include <bitset>
#include <iostream>
#include <limits>
using namespace std;
int main( )
{
// Read a binary number into a bitset
cout << "Enter a binary number: ";
bitset< numeric_limits<unsigned long>::digits > bits;
cin >> bits;
unsigned long decimal_equivalent = bits.to_ulong();
cout << "Binary number: " << bits << "\nDecimal equivalent: " << decimal_equivalent;
}</source>

==Reset bit in a bitset==

<source lang="cpp">#include <bitset>
#include <iostream>
using namespace std;
int main( ){
const int num_lights = 15;
const bitset<num_lights> outside( 0xf );
const bitset<num_lights> inside( 0xff0 );
const bitset<num_lights> driveway( 0x7000 );
bitset<num_lights> lights;
for( int i = 0; i < num_lights; i +=2 )
lights.reset( i );
cout << lights;
}</source>

==Test value in a bitset==

<source lang="cpp">#include <bitset>
#include <iostream>
using namespace std;
int main(int argc, char** argv){
bitset<10> myBitset;
myBitset.set(3);
myBitset.set(6);
myBitset[8] = true;
myBitset[9] = myBitset[3];
if (myBitset.test(3)) {
cout << "Bit 3 is set!\n";
}
cout << myBitset << endl;
return (0);
}</source>

==Use bitset with enum together==

<source lang="cpp">/* The following code example is taken from the book
* "The C++ Standard Library - A Tutorial and Reference"
* by Nicolai M. Josuttis, Addison-Wesley, 1999
*
* (C) Copyright Nicolai M. Josuttis 1999.
* Permission to copy, use, modify, sell and distribute this software
* is granted provided this copyright notice appears in all copies.
* This software is provided "as is" without express or implied
* warranty, and with no claim as to its suitability for any purpose.
*/
#include <bitset>
#include <iostream>
using namespace std;
int main()
{
/* enumeration type for the bits
* - each bit represents a color
*/
enum Color { red, yellow, green, blue, white, black, //...,
numColors };
// create bitset for all bits/colors
bitset<numColors> usedColors;
// set bits for two colors
usedColors.set(red);
usedColors.set(blue);
// print some bitset data
cout << "bitfield of used colors: " << usedColors
<< endl;
cout << "number of used colors: " << usedColors.count()
<< endl;
cout << "bitfield of unused colors: " << ~usedColors
<< endl;
// if any color is used
if (usedColors.any()) {
// loop over all colors
for (int c = 0; c < numColors; ++c) {
// if the actual color is used
if (usedColors[(Color)c]) {
//...
}
}
}
}</source>
<pre class=codeResult>bitfield of used colors: 001001
number of used colors: 2
bitfield of unused colors: 110110</pre>

==write a decimal integer as a binary number==

<source lang="cpp">#include <bitset>
#include <iostream>
#include <limits>
using namespace std;
int main( )
{
// write a decimal integer as a binary number
int num = 100;
cout << "\n\nDecimal number: " << num << "\tBinary equivalent: " << bitset<8>(num) << endl;
}</source>

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