boolean in C++

A boolean data type in C++ is defined using the keyword bool . 
Although any numerical value can be assigned to a boolean variable in C++, all values other than 0 are considered to be true and stored as 1, while 0 is considered to be false .
```
bool b1 = true;
bool b2 = false;
cout << b1;  // Outputs 1 (true)
cout << b2;  // Outputs 0 (false)
```