Basic C++

Input and Output

• A data stream is a sequence of data.
• An input stream is data for the program to use.
• cin is an input stream bringing data from the keyboard
• The extraction operator (>>) removes data to be used
• Example:
• cin >> number_of_bars;

• An output stream is the program's output.
• cout is an output stream sending data to the monitor.
• The insertion operator "<<" inserts data into cout
• Example:
• cout << number_of_bars << " candy bars\n";
• Showing decimal places:
• fixed point notion - cout.setf (ios :: fixed);
• To specify that the decimal point will always be shown - cout.setf (ios :: showpoint);
• To specify that two decimal places will always be shown - cout.precision (2);

Data Types

• Type char - can be any single character from the keyword.
• char constants are enclosed in a single quote.
• char letter = 'a';
• Type string - is a class, different from the primitive data type.
• Requires the following be added to the top of the program:
• #include <string> 
• string are enclosed in a double quote:
• string name = "Apu Nahasapeemapetilon";
• Type Compatibilities - in general store values in variables of the same type.
• Variables of type double should not be assigned to variable of type int.
• Integer values can normally be stored in variables of type double.
• It is possible to store char values in integer variables:
• int value = 'A';
• It is possible to store int values in char variables:
• char letter = 25;
• Values of type bool can be assigned to int variables
• True is stored as 1 
• False is stored as 0
• Values of type int can be assigned to bool variables
• Any non-zero integer is stored as true
• Zero is stored as false