Introduction to Programming Concepts

Chapter 9-12 Computer Programming

• Objectives include program and programming, algorithms & programs, software life cycle, computer language generations, and flowchart.

Program and Programming

• Program: A set of instructions written in a programming language that directs a computer to perform specific tasks in a predefined manner. It aims to solve a specific problem.
• Programming: The process of providing instructions to a computer that dictates the processor's actions. It involves creating step-by-step instructions. Planning is essential before writing a program, ensuring a deep understanding of the problem.

Algorithms and Programs

• Algorithm: A set of steps to solve a problem, independent of any programming language. It's the logical core.
• Program: An algorithm expressed in a specific programming language's instructions.

Algorithm Example

• Maximum of two numbers:
  • Input two numbers.
  • Compare the two numbers.
  • Output the greater number.
• Average of three numbers:
  • Input three numbers.
  • Add the three numbers.
  • Divide the sum by 3.
  • Output the result.

Software Development Lifecycle

• A cyclical process involving steps like feasibility study, requirements analysis, design, coding, system test, deploy, and operate/maintain.

Software Life Cycle

• What: Requirements gathering, problem definition.
• How: Analysis and design (programming techniques).
• Do it: Coding.
• Test: Testing.
• Use: Implementation and maintenance.

Computer Language Generations

• Machine language: Programs written in binary code (0s and 1s) for direct execution by the computer's hardware.
• Assembly languages: Use mnemonics (symbols) to represent machine instructions. Requires an assembler.
• High-level languages: Languages like C, Pascal, and Java; easier to read and write than assembly. Requires a compiler.
• Very high-level languages (4GLs): Non-procedural languages; the programmer specifies desired results, and the language determines the solution strategy.
• Natural languages: Programs written in human-readable language.

Machine Language

• Programs and memory locations are written in strings of 0s and 1s.
• Machine languages are difficult to write and debug.
• Each computer has its own machine language.

Assembly Languages

• Use names instead of binary addresses.
• Require an assembler to translate to machine language.
• Still used in specialized programming tasks.

High-Level Languages

• Allow programmers to focus on solving problems instead of directly managing hardware.
• Programs are written and debugged more quickly.
• Requires a compiler to translate the program to machine language.

Very High-Level Languages

• Also called fourth-generation languages (4GLs).
• Non-procedural languages.
• Programmers focus on desired results, with the language determining the solution.
• Increased programmer productivity compared to third-generation languages.

Natural Languages

• Resemble spoken or written English.
• Programs use a natural syntax, different from traditional programming syntax rules.
• The language translates instructions into code that the computer can execute.

Major Programming Languages

• FORTRAN
• COBOL
• BASIC
• RPG
• Visual Basic
• C
• Java

Object-Oriented Languages

• C++
• Java
• C#
• Visual Basic

Basic Translation Process

• Source program
• Preprocessor directives to produce a translation unit
• Check translation unit for legal syntax
• Compile translation unit into an object file
• Link object file with standard object file and other object files to produce an executable unit

Library Header Files

• Typically contain function prototypes.
• Often describe an interface for the library components.
• Might contain class definitions or object definitions.
• Example: iostream header file containing cout and cin definitions.

Major Data Types

• int (integer): Positive and negative whole numbers.
• float, double (real): Decimal numbers.
• char: Alphanumeric characters and symbols.
• bool (boolean): Logical value (true/false).

Constants

• Literal constants: Explicit numbers or characters.
• Named constants: Locations in memory with a name, used to store unchanging values.

Statements

• A statement is an instruction to the computer, like cout << "some message";
• Statements must typically end with a semicolon (;).

Variables

• Variables are named memory locations where data can be stored and modified.
• Variable declaration includes specifying data type and variable names.

Arithmetic Operators

• Addition (+): Adds operands.
• Subtraction (-): Subtracts the second operand from the first.
• Negation (-): Negates an operand.
• Multiplication (*): Multiplies operands.
• Division (/): Divides the first operand by the second.
• Modulus (%): Finds the remainder of integer division.

Compound Assignment

• A shorthand way of updating a variable's value.
• Example: x+=5; is equivalent to x = x + 5;

Increment/Decrement

• Increment operator (++): Increases the value of a variable by 1.
• Decrement operator (--): Decreases the value of a variable by 1.
• Prefix and postfix versions affect the order of evaluation.

Arithmetic Expressions

• Combining constants, variables, and arithmetic operators to form expressions.
• The result type depends on the operands and operations.
• Example: 7 / 3 (integer operation)

Integer Division

• Integer division results in an integer quotient.
• Example 10 / 3 = 3 (Remainder is truncated)

Mod

• Finds the remainder of integer division.
• Example: 10 % 3 = 1

Operators and Precedence

• Operators have different priorities in sequence of operation during expression evaluation.
• Parentheses override standard precedence.

Relational Operators

• These compare values and return 1 (true) or 0 (false).
• Example: x > y (evaluates to 1 if x is greater than y, 0 otherwise).

Logical Operators

• AND (&&): Returns true only if both sides are true.
• OR(||): Returns true if either side is true.
• NOT (!): Negates a Boolean expression.

Operator Hierarchy

• A definite order of evaluating operators in expressions.
• Parentheses have the highest precedence.

Standard Functions

• Predefined functions in C++ libraries that manipulate data types.
• Example: abs(), strlen(), sqrt().

Function Invocation

• Calling a previously defined function to perform actions on stored data.
• Results returned may be stored or displayed.

Function Communication

• Parameter lists pass data into functions to be used in the functions.
• Returned values can be stored and used in the calling program.

Input/Output

• cout operator sends data (text or values) to the standard output device (like a monitor).
• cin operator reads input from the standard input device (like a keyboard).

Output Examples

• Displaying various data types (integers, floats, and strings) through cout.

Input Examples

• Reading input from the user using the cin operator.

Extraction Operator

• Accesses data from an input device (like a keyboard).
• Ignores whitespace characters.

Insertion Operator

• Writes data to an output device (like a monitor).

Compound Statements

• A group of statements that is treated as a single statement by the compiler, usually enclosed within curly brackets {}.

Forms of Boolean Expressions

• Boolean expressions involve arithmetic and relational operators.
• Relational operators, like >, <, >=,<=, ==, !=, evaluate to Boolean values.

Boolean Expression Examples

• Evaluating Boolean expressions using example data.

Truth Tables

• Illustrates how Boolean operators evaluate to true or false.

Short Circuiting

• Optimizing Boolean expression evaluation by avoiding unnecessary operations.

C++ Operator Hierarchy

• Explicit rules for the order in which operators are evaluated in expressions.

Loop Design Considerations

• Considerations for defining loops with various conditions and considerations.

While Loop

• A repeated set of statements that is executed as long as a specific condition is true.

Do...While Loop

• Similar to the While Loop but executed at least once.

For Loop

• Used for a fixed number of iterations, it's often used for counting loops.

Event Controlled Loop

• Loops execute until a specific event is detected or until an object changes its state.

Count Controlled Loops

• Loops that run a set number of times, controlled by a counter variable.

Nested if Statement

• Using if-else statements within other if-else structures for conditions.

Nested if Examples

• Illustrating the use of nested if statements by providing examples.

Switch Statement

• A conditional statement for matching specific values against a set of possibilities.

Switch Examples

• Providing examples using switch statements.

Example Program using switch case

• Detailed examples of switch case programming.

Control Flow

• Order of statement execution in the program.

Selection, if...else

• Structure to control execution based on conditional expressions.

Output Examples

• Specific example programs that output specified outputs through the use of C+ code.

Input Examples

• Demonstration of reading data from input devices.

This quiz covers fundamental concepts in programming languages, including algorithms, programming language generations, and the Software Life Cycle. Test your understanding of key definitions, steps in problem-solving, and the characteristics of different coding practices. Ideal for beginners looking to solidify their knowledge in computer programming.