Chap 1: What is a program made of?

C++ program requires compiler, interpreter and linker in order to make the program run.

• True

• False

Answer explanation

C++ requires compiler and linker. Interpreter is used in language like Python, Javascript and Php.

Compiler translates code from a high-level programming language (like C++, Java) into machine readable code.

Interpreters run through a program line by line and execute each command.

Generally, high level language requires more memory.

Compiler and interpreter's goals are different.

• True

• False

Answer explanation

They are both to convert human written code into computer readable code.

C++ is a compiled language.

• True

• False

Answer explanation

C++ is a compiled language. Python is an interpreted language. What can you tell generally the difference in the environment?

What pre-processor is for?

• To prepare the compiler to process the code which has been written

• To convert source program/code into machine language

• To convert directive lines in the source code file to take specific actions

• To perform preliminary operations on C++ files before they are passed to the compiler.

Answer explanation

The preprocessor is a program that is invoked by the compiler to process code before compilation.

The preprocessor commands for that program, known as directives, are lines of the source file beginning with the character # , which distinguishes them from lines of program text.

Linker is necessary for a compiled language to...

• Connect the hardware with the instruction specified in the program/code

• Use the machine instruction to execute the command given

• Use the program written to execute the command in the program

• Change back the machine instruction into human readable language

Answer explanation

"Use the program written to execute the command in the program" is for interpreter.

"Change back the machine instruction into human readable language" is for compiler and interpreter.

In every programming language, the following are elements one would have:

• Keywords

• Programmer-defined Identifiers

• Operators

• Punctuation

• Syntax

Answer explanation

These are the basic elements of any programming languages.

Keywords are also known as reserve word.

• True

• False

Answer explanation

Another name for keywords is reserve word. These word has special meaning in the language which it cannot be used as a variable or other non-related purposes.

Identify which of the following are reserve words for C++?

• number

• int

• double

• symbol

• return

Answer explanation

It may be daunting to think you have to memorise all the keywords but it just take practice to remember them all.

Among the labelled items, identify which are C++ keywords

• A

• B

• D

• E

• F

Answer explanation

Keywords have a special meaning by the C++ compiler and cannot be used for any other purpose.

What is a programmer-defined identifiers?

• Can use reserve words

• Names made up by the programmer

• Can be variables used in the program

• Can be an address of a memory slot

Answer explanation

Programmer-defined identifiers are name created by programmer which is not refering to any C++ language reserve words. It can be used to represent variable, memory location, a location to a memory location, function and etc.