Lesson 3 Getting Started with C Programming

What is the purpose of comments in a C++ program?

• To store data

• To increase program speed

• To describe what the code does

• To execute code

Answer explanation

Comments in a C++ program are used to describe what the code does, making it easier for others (and the original author) to understand the logic and purpose of the code. They do not affect execution or performance.

Which symbol is used to start a single-line comment in C++?

• //

• /*

• #

• --

Answer explanation

In C++, single-line comments start with the symbol '//'. This allows programmers to add notes or disable code on a single line. The other options are used for different types of comments or directives.

What does the escape sequence '\n' do in a string?

• Inserts a backslash

• Inserts a space

• Inserts a new line

• Inserts a tab

Answer explanation

The escape sequence '\n' is used in strings to insert a new line. This means that when it is encountered, the text following it will start on a new line, making it the correct choice among the options provided.

What is a banner in a C++ program?

• A type of error

• A variable declaration

• A set of comments at the beginning of the program

• A function to display output

Answer explanation

In C++, a banner typically refers to a set of comments at the beginning of the program that provides information about the program, such as its purpose, author, and date. This helps in understanding the code better.

Which of the following is a type of error in C++?

• All of the above

• Syntax error

• Logical error

• Run-time error

Answer explanation

In C++, errors can be categorized into syntax errors (code mistakes), logical errors (incorrect logic), and run-time errors (issues during execution). Therefore, 'All of the above' is the correct choice as it encompasses all types of errors.

What does the 'cout' statement do in C++?

• It creates a comment

• It declares a variable

• It outputs data to the console

• It compiles the program

Answer explanation

The 'cout' statement in C++ is used to output data to the console. It is part of the iostream library and allows programmers to display text and variables to the user, making it essential for interactive applications.

Which escape sequence is used to display a double quote?

• \"

• \n

• \t

• \'

Answer explanation

The escape sequence for displaying a double quote in strings is \", which allows the quote to be included without ending the string. Other options like \n (newline), \t (tab), and \' (single quote) serve different purposes.

What type of error occurs when the program violates grammar rules?

• Syntax error

• Compilation error

• Logic error

• Run-time error

Answer explanation

A syntax error occurs when the program violates grammar rules, preventing it from being compiled. This is distinct from compilation errors, logic errors, and run-time errors, which arise at different stages of program execution.

What is the purpose of the 'endl' manipulator?

• To end a program

• To create a comment

• To insert a new line and flush the output buffer

• To declare a variable

Answer explanation

The 'endl' manipulator is used in C++ to insert a new line in the output stream and also flush the output buffer, ensuring that all output is displayed immediately. This makes it the correct choice among the options.

What does a run-time error indicate?

• A missing variable declaration

• A mistake in the code syntax

• An error that occurs during program execution

• A logical flaw in the program

Answer explanation

A run-time error indicates an issue that arises while the program is running, such as trying to divide by zero or accessing a null object. This distinguishes it from syntax errors, which occur before execution.