Comments

Comments in programming are parts of code that are ignored. It’s a good rule to use them to improve the readability of your code with specific descriptions of what a certain part of the code does. Comments also help when you want to test a certain part of the program without deleting the other code.

To mark the line(or part of the line) as a comment, begin the respective string with //.

For example, in this case, the line which outputs the message "Hello!" will be ignored:


              123456789
            
#include &lt;iostream&gt;
using namespace std;
 
int main() {
 &nbsp&nbsp&nbsp&nbsp // cout << "Hello! \n";
 &nbsp&nbsp&nbsp&nbsp cout << "I love C++! ";
 &nbsp&nbsp&nbsp&nbsp cout << "Goodbye!";
&nbsp&nbsp&nbsp&nbspreturn 0;
}

This type of comment is also good for code explanation:

If you want the compiler to ignore several lines use multi-line comments. They start with /* and end with */:


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#include &lt;iostream&gt;
using namespace std;
 
int main() {
 &nbsp&nbsp&nbsp&nbsp&nbsp/* cout << "Hello!";
 &nbsp&nbsp&nbsp&nbsp cout << "I love C++! "; */ 
 &nbsp&nbsp&nbsp&nbsp cout << "Goodbye!";  // Print the message
 &nbsp&nbsp&nbsp&nbsp return 0;
}

Everything was clear?

Thanks for your feedback!

Section 1. Chapter 4

Introduction to C++

Comments

The code must only print the message: "I have learned C++ basics!". Fill gaps in the code: