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Introduction to C++

bookComments

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 <iostream>
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;
}
copy

This type of comment is also good for code explanation:

cout << "Goodbye!";  // Print the message

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


              
123456789

            
#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;
}
copy
question-icon

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

#include <iostream>
using namespace std;

int main() {
     cout << "Hello!\n";
    cout << "World!\n";
    cout << "I have learned C++ basics! \n";   Print the message
    return 0;
}
I’m learning C++!

Click or drag`n`drop items and fill in the blanks

Everything was clear?

How can we improve it?

Thanks for your feedback!

SectionΒ 1. ChapterΒ 4

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bookComments

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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;
}
copy

This type of comment is also good for code explanation:

cout << "Goodbye!";  // Print the message

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


              
123456789

            
#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;
}
copy
question-icon

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

#include <iostream>
using namespace std;

int main() {
     cout << "Hello!\n";
    cout << "World!\n";
    cout << "I have learned C++ basics! \n";   Print the message
    return 0;
}
I’m learning C++!

Click or drag`n`drop items and fill in the blanks

Everything was clear?

How can we improve it?

Thanks for your feedback!

SectionΒ 1. ChapterΒ 4
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