C++ Programming - Basic Elements (Part C)

C++ Programming - Basic Elements (Part C)

• Putting data into variables:
  • Variables receive data using assignment statements (like variable = expression;) or input statements (using cin).
  • Interactive input involves the user typing data, which the computer receives from the keyboard.
  • Input statements use cin >> variable1 >> variable2, which get data from the standard input.
  • Example: cin >> miles; reads input and stores it in the variable miles.
  • Example: cout << "Please insert the value of miles: "; prompts the user for input
  • Example: double miles; declares a variable miles of type double.
• Assignment statements:
  • The basic form is variable = expression;.
  • Variables on the left side get the value calculated on the right side of the equation.
  • Example: int counter = 5; declares and initializes a variable counter to 5.
• Input (read) statements (using cin):
  • cin >> variable reads input from the user and assigns it to the variable. Spaces, tabs, or returns act as separators.
  • Example: cin >> feet >> inches; reads two integers separated by a space.
  • Using getline to read strings: getline(cin, name); reads the entire line entered by the user, which is now stored in string variable name. Use this for names, or multiple words. This function correctly handles multiple words in a single line of input.
  • Example (when reading a string including multiple words): cout << "Please enter your name: "; getline(cin, name); cout << "Your name is: " << name << endl;

Increment and Decrement Operators

• Increment operators (++) increase a variable's value by 1.
  • counter++; is the post-increment operator (increments after the expression is evaluated).
  • ++counter; is the pre-increment operator (increments before the expression is evaluated).
• Decrement operators (--) decrease a variable's value by 1.
  • counter--; (post-decrement)
  • --counter; (pre-decrement)
• These operators can be used within expressions and calculations, impacting variable values in different ways.

Example usage

• Example code demonstrates the correct use of cin and cout to prompt the user and get data from the command line.

This quiz focuses on the foundational aspects of C++ programming, including how to put data into variables and the usage of assignment and input statements. You'll explore examples of variable declarations and read methods to enhance your understanding of interactive input. Test your knowledge of these key concepts in C++ programming.