Variable Type bool

1. The C++ reserved word to specify variables of the Boolean type is bool.
   
   
2. Boolean variables can only take on 2 possible values: true and false.
   
   
3. They can be declared and initialized as follows:
   bool is_feeling_lucky = true;
   Note that the reserved words true and false are not enclosed by single or double quotes.
   
   
4. In the input and output of Boolean variables, 1 is used to represent true, and 0 for false.
   
   
5. Example: the code
   
   bool is_stolen_money_spent;
   cout << "Did you use up all the money that you stole from me?\n";
   cin >> is_stolen_money_spent;
   cout << "The answer is: "
            << is_stolen_money_spent << endl;
   
   yields the following output:
   
   Did you use up all the money that you stole from me?
   1
   The answer is: 1
   
   
6. Boolean variables and expressions are often used in making decisions and in controlling the repetition of loops.