C++ Example #1

// helloworld.cpp
//
// compile: g++ -Wall -o helloworld helloworld.cpp

#include <iostream>

int main()
{
  std::cout << "Hello World!" << std::endl;

  return 0;
}

helloworld.cpp

• Comments must be preceeded by //.
• Compile with the g++ compiler.
• The main() function is where program execution begins ... all C/C++ programs must have a main function.
• cout is defined in the C++ iostream library and must be scoped by its namespace (std::).
• cout is the standard output stream in C++ ... it replaces printf() in C.
• endl is defined in the C++ iostream library and produces a line feed.
• « is the output, or extraction, operator.
• The return statement causes the main() function to return with the error code argument (0 = no errors) provided.