Chapter 3 Computer Science 12 - Federal Board PDF

# Object Oriented Programming in C++ ## Defining Terms * **Program:** A set of instructions that performs a specific task when executed by a computer. * **Header file:** Contains information required by the program. * **Reserved words:** Special words reserved by the programming language for speci...

# Object Oriented Programming in C++ ## Defining Terms * **Program:** A set of instructions that performs a specific task when executed by a computer. * **Header file:** Contains information required by the program. * **Reserved words:** Special words reserved by the programming language for specific purposes. * **Statement terminator:** Marks the end of a statement (semicolon). * **Comments:** Explanatory statements that help the reader understand the code. * **Constant:** A value that does not change during execution. * **Variable:** A name of memory location that stores data. * **Escape sequence:** Special characters that control output on the output device. * **Operator:** A symbol that tells the computer to perform a specific task. * **Assignment operator:** Assigns a value to a variable (equals sign). * **Arithmetic operator:** Performs arithmetic operations (addition, subtraction, multiplication, division). * **Relational operator:** Compares two values of the same type. * **Logical operator:** Combines two or more conditions (AND, OR, NOT). * **Compound expression:** Combines two or more conditions using logical operators. * **Type casting:** Converts a data type to another. * **Preprocessor directive:** Used to include a header file. * **Manipulator:** Modifies the output in various ways. ## Concepts ### Data types C++ supports the following data types: * **Integer:** Stores whole numbers. * `int`: 4 bytes, -2147483648 to 2147483647 * `unsigned int`: 4 bytes, 0 to 4294967295 * `short int`: 2 bytes, -32768 to 32767 * `unsigned short int`: 2 bytes, 0 to 65535 * `long int`: 4 bytes, -2147483648 to 2147483647 * `unsigned long int`: 4 bytes, 0 to 4294967295 * **Floating Point:** Stores numbers with a fractional part. * `float`: 4 bytes, -3.4E-38 to 3.4E+38 (6 digits of precision) * `double`: 8 bytes, -1.7E+308 to 1.7E+308 (15 digits of precision) * **Character:** Stores a single character. * `char`: 1 byte ### Constants A constant is a value that does not change during execution. ``` const int AGE = 34; ``` ### Variables A variable is a name of a memory location that stores data. ``` int x,y,z; ``` ### Operators Operators perform specific actions based on operands. * **Arithmetic Operators:** * `+`: Addition * `-`: Subtraction * `*`: Multiplication * `/`: Division * `%`: Modulo (remainder) * **Assignment Operators:** * `=`: Assigns a value to a variable * `+=`: Adds and assigns * `-=`: Subtracts and assigns * `*=`: Multiplies and assigns * `/=`: Divides and assigns * `%=`: Modulo and assigns * **Increment/Decrement Operators:** * `++`: Increments by one * `--`: Decrements by one * **Relational Operators:** * `==`: Equal to * `!=`: Not equal to * `<`: Less than * `>`: Greater than * `<=`: Less than or equal to * `>=`: Greater than or equal to * **Logical Operators:** * `&&`: AND * `||`: OR * `!`: NOT * **Ternary Operators:** * `?:`: Conditional Operator ### Functions * **`cout`:** Outputs data on the screen. * **`cin`:** Inputs data from the keyboard. * **`getch()`:** Reads a single character from the keyboard, without pressing Enter. * **`getche()`:** Reads a single character from the keyboard, and displays it on the screen. * **`gets()`:** Inputs a string from the keyboard. * **`puts()`:** Outputs a string to the screen. ### Escape Sequences Escape sequences are special characters that control formatting. * `\a`: Alert (beep) sound * `\b`: Backspace * `\n`: Newline * `\r`: Carriage return * `\t`: Tab * `\\`: Backslash * `\'`: Single quote * `\"`: Double quote ### Manipulators * **`endl`:** Inserts a newline and flushes the output buffer. * **`setw(n)`:** Sets the minimum field width. ## Example Programs ### Program 1: Sum and Product of Three Integers ```c++ #include<iostream.h> #include<conio.h> void main() { int x,y,z,sum,prod; cout<<"\nEnter first number:"; cin>>x; cout<<"\nEnter second number:"; cin>>y; cout<<"\nEnter third number:”; cin>>z; sum=x+y+z; prod=x*y*z; cout<<"\nSum="<<sum; cout<<"\nProduct="<<prod; getch(); } ``` ### Program 2: Area of a triangle ```c++ #include<iostream.h> #include<conio.h> void main() { float base,height,area; cout<< "\nEnter the base:"; cin>>base; cout<< "\nEnter the height:"; cin>>height; area=(base*height)/2; cout<< “\nThe area of triangle is "<<area; getch(); } ``` ### Program 3: Output Formatting with Manipulators ```c++ #include<iostream.h> #include<conio.h> #include<iomanip.h> void main() { int price1=8540,price2=325,price3=27800; cout<< "Product" <<setw(10)<< "Price"<<endl << "Hard disk" <<setw(10)<<price1<<endl << "Mouse" <<setw(10)<<price2<<endl << “Computer" <<setw(10)<<price3<<endl; getch(); } ``` ## Header Files | Header File | Description | |---|---| | `iostream.h` | Basic input/output operations (cin, cout). | | `conio.h` | Console input/output, manages input/output for console based applications. | | `math.h` | Basic mathematical operations (sqrt, pow). | | `string.h` | String manipulation functions (strcmp, strcpy). | | `iomanip.h` | Manipulators (setw, endl, setprecision). | | `time.h` | Date and time operations. | ## Precedence of Operations The operators are evaluated in the following order of precedence: 1. `*`, `/`, `%` 2. `+`, `-` 3. `<`, `<=`, `>`, `>=` 4. `==`, `!=` 5. `!` (not) 6. `&&` (and) 7. `||` (or) 8. `=`, `+=`, `-=`, `*=`, `/=`, `%= ` ## Home Assignments 1. Write a program that reads four integers and prints their sum, product and average. 2. Write a program that reads length and breadth of a rectangle and prints its area. 3. Write a program that reads temperature in Fahrenheit and prints its equivalent temperature in Celsius using the formula: `c = 5/9(f-32)`. This Markdown document provides a structured format for the content of the Object Oriented Programming in C++ document or image. This guide covers key definitions, concepts, and even example programs. Further exercises and home assignments are also provided to expand upon the learned concepts.