Output in C++
Text Output
Notice how we output "Hello World!"? In fact, you can output anything you like by changing the words in the double quotes! It's that easy!
Example:
cout << "Whatever, just text.";
Numbers Output
Replacing the double quotes with a number results in the number being outputted. This works with not only integers, but also decimals. Note that it will automatically truncate the number until six-seven digits remain. This is due to the method that C++ stores decimals and we will cover that later.
Example:
cout << 123456789.123456789;outputs
1.23457e+08, meaning \(1.23457 \times 10^8\).
cout << 0.123456789;outputs
0.123457.
Escape Characters
What happens of you try to output a newline? C++ ignores whitespace, so
cout << "does not work. To include a newline, you need to escape it with a backslash.
";
cout << "\n";outputs a newline. This is called "escape characters", meaning the character combination changes its meaning. A few common ones include:
| Character | Meaning |
|---|---|
| \n | Newline |
| \t | Tab |
| \r | Carriage Return |
| \v | Vertical Tab |
| \f | Form Feed |
| \b | Backspace |
| \a | Alert |
| \\ | Backslash |
| \" | Double quote |
| \' | Single quote |
| \% | Percent sign |
There is one more trick of outputting these characters: Raw String Literals. Introduced in C++11 (a version published in the year 2011), these string literals ignore no whitespace and perform no escaping -- they are outputted just as they are. They are used like so:
R"(STRING_CONTENT)".
Example:
cout << R"(this is a \n raw string literal)";will output
this is a \n raw string literal
Now head on to the next page to learn about variables!