C++ Hello World
C++ Hello World
Let’s break up the following code to understand it better:
Example
#include <iostream>
using namespace std;int main() {
cout << “Hello World!”;
return 0;
}
Example explained
Line 1: #include <iostream>
is a header file library that lets us work with input and output objects, such as cout
(used in line 5). Header files add functionality to C++ programs.
Line 2: using namespace std
means that we can use names for objects and variables from the standard library.
Line 3: A blank line. C++ ignores white space.
Line 4: Another thing that always appear in a C++ program, is int main()
. This is called a function. Any code inside its curly brackets {}
will be executed.
Line 5: cout
(pronounced “see-out”) is an object used together with the insertion operator (<<
) to output/print text. In our example it will output “Hello World”.
Note: Every C++ statement ends with a semicolon ;
.
Note: The body of int main()
could also been written as:
int main () { cout << "Hello World! "; return 0; }
Remember: The compiler ignores white spaces. However, multiple lines makes the code more readable.
Line 6: return 0
ends the main function.
Line 7: Do not forget to add the closing curly bracket }
to actually end the main function.