Work with integers as binary in C++

Sometimes we need to work with integers in binary format and manipulate individual bytes in their binary representation. Here I will show two ways we can work with integers this way.

First way is to use ordinary int type.

First let’s create two variable in binary format:

int x = 0b00100;
int y = 0b00101;

Here we use use binary literals with ‘b’ character. These binary literals were standardized in C++14.

We can add two values like that

int z = a + b;

Result is 0x01001 or 9

If we print value with cout we will get decimal representation

cout << z << endl;
9

To print the result in binary foramt we need to use bitset library. Import it

#include <bitset>

and print the variable

cout << std::bitset<6>(z) << endl;

Here first non-type template parameter specifies the number of bits to store. 6 in our case.

Second way is to use byte type available since C++17. Notice according to documentation that it is not a character type and is not an arithmetic type. A byte is only a collection of bits, and onliy bitwise operators defined for it. Thus arithmetic ones can’t be used for it.

Include header file

#include <cstddef>

Create byte object using regular int

byte myByte{ 2 };

Apply 2-bit left shift

myByte <<= 2;

and print result as int:

cout << to_integer<int>(myByte) << endl;

We can initialize variable using binary literal

byte byte1{ 0b0011 };
byte byte2{ 0b1010 };

Apply bitwise OR and AND operations

byte byteOr = byte1 | byte2;
byte byteAnd = byte1 & byte2;

and print result as int:

cout << to_integer<int>(byteOr) << endl;

That’s all you need to work with binary numbers in C++.