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Introduction

Computer Program

- Sequence of statements whose objectives is to accomplish a task

Programming

- Process of planning

The Basics of a C++ Program

Function: Collection of statements; when executed, accomplish something.

- May be predefined or standard

Syntax: rules that specify which statements are legal

Programming language: a set of rules, symbols, and special words

Semantic rule: meaning of instruction

Comments

- Comments are for the reader, not the compiler

- Two types

Single line (//)

Multiple line (/*)

Special Symbols

+ - * / . ; ? , < = ! = == > =

Reserved Words (Keywords)

- Reserved words, keywords or word symbols

Identifiers

- Consists of letters, digits, and the underscore character

- Must begin with a letter or underscore

- C++ is case sensitive

- Two predefined identifiers are cout and cin

- Unlike reserved words, predefined identifiers may be redefined, but it is not a

good idea

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Legal Identifiers in C++:

- first

- conversion

- payRate

- there can be no space

- no symbols

- cannot begin w/ a number

Whitespaces

- every C++ Program contains whitespaces

include blanks, tabs, and newline characters

- used to separate symbols, reserved words, and identifiers

- proper utilization of whitespaces is important

can be used to make the program readable

Data Types

Data type: set of values together with a set of operations

Simple Data Type

- integral: integers

- floating-point: decimal

- enumeration type: user defined

Integral Data types:

- char, short, int, long, bool

- unsigned char, unsigned short, unsigned int, unsigned long

bool true and false

- different compiler s may allow different ranges of values

Floating-Point Data Tyes

- uses scientific notations to represent real numbers

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- float: represents any real number (4bytes) 7SF

- double: (8byes) 15SF

Arithmetic Operators and Operator Precedence

- + -/*%

- Can be unary or binary

- All operations inside the () are evaluated first

- *,/, % same level

- +, - same level

- Left to Right (associativity)

Expressions

- If all operands are integers (integral expression)

- If all operands are floating point (floating-point expression)

- Mixed expressions (combination)

Evaluation Rules:

- If same types the result would be the same

- When different int is changed to double

- Evaluated according to precedence

Type Conversion (Casting)

- Cast operator - static_cast ( )

- implicit type coercion - automatic

string Type

- programmer-defined type supplied in ANSI/ISO Standard C++ library

- sequence of zero or more characters

- enclosed in double quotation marks

- null: a string w/ no characters

- each character has a relative position in string

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- length of a string is the number of characters in it