1. C++ Basics Structure of a Program

2. C++ Source Code Plain text file Typical file extension .CPP Must compile the C++ source code without errors before run the program Consist of  #include statement  class declaration (optional)  variables and constants declaration (optional)  int main() function and any other functions

3. // my first program in C++ #include using namespace std; int main ( ) { cout << "Hello World!"; return 0; } Output monitor: Hello World!

4. Comments // my first program in C++ Any descriptions or explanations of the program or code  Will not be compiled or executed by computer  Begin with // (double slashes) – a line comment  Can be located any place in the program  Block comment ( /* … */ ) – contains a multiple- line comment

5. Directives for Preprocessor #include #include – tell the compiler’s preprocessor to include library files before compiling the source code  usually standard library file, or custom class file  for standard library; “ ” for custom file  No semi-colon (;) at the end of the line

6. Using Namespace using namespace std; Namespace – collection of name definitions std – the location where all C++ library elements are declared  To use the library elements, using statement should be added  Located below all #include statements  Must put semi-colon at the end of the line

7. Beginning of a Program int main ( ) is the beginning of any C++ program  Only one int main ( ) function is allowed in a source code  Immediately followed by a pair of curly braces ( { } ) which holds the C++ instructions  If one or more custom functions are declared, int main ( ) function is usually located as the last function  C++ is case-sensitive  if and IF are different

8. Standard Input and Output cout << "Hello World!"; cout – standard output (to console or monitor)  Use operator << to separate each item to display cin – standard input (from keyboard)  Use operator >> to a variable Each C++ statement must ends with a semi- colon (;)

9. Text Strings A series of alpha-numeric characters (including special characters)  Contains no numeric value  Must be enclosed by a pair of quotations – usually double, but in some case, single quotations  Every blank space counts inside “ ”  Double quotation without any character or blank space means ‘blank’ or ‘Null’ text string

10. Return Statement Return – cause the main function or any custom function to finish and return a value  return 0; - main function’s return value is declared as int, so a numeric value 0 is returned (will not be used at all)

11. System Pause Statement System statement – controls a system functioning  Enclosed by system ;  Some software does not pause the result console window after the program execution  Pause the screen until any key press on the keyboard