# VARIABLES AND TYPES CITS1001

Size: px
Start display at page:

Transcription

1 VARIABLES AND TYPES CITS1001

2 Scope of this lecture Types in Java the eight primitive types the unlimited number of object types Values and References The Golden Rule

3 Primitive types Every piece of data that is stored or moved around in Java must have a type Java supplies eight primitive types for the most fundamental pieces of data short! int! long! float! double! byte boolean! char!

4 Integer primitive types Four of the types are used for storing whole numbers Each occupies a fixed amount of memory byte uses 1 byte and stores integers from -128 to 127 short uses 2 bytes and stores integers from to int uses 4 bytes and stores integers from to long uses 8 bytes and stores integers from to (that is 2 63 to )

5 Floating point primitive types There are two types used for floating point values in other words, numbers with decimal points float uses 4 bytes and stores floating point numbers, positive or negative, in the range 1.4e-45 to e38 double uses 8 bytes and stores floating point numbers, positive or negative, in the range 4.9e-324 to e308

6 Declaring variables In Java, all variables must be declared before they are used The declaration specifies the type and name of the variable When a primitive variable is created, a fixed amount of memory is set aside for that variable byte b;! double temp;! b! int balance;! temp! balance!

7 Assignments to numeric types An assignment sets the value of a variable int x;!!// this is a declaration! x = 100;! Here are some legal assignments int x;! double y;! double z;!! x = 200;! y = ;!!// this is an assignment! z = 23e5;!// this is scientific notation

8 Typecasting The compiler will warn you if you attempt to use a smallersized variable than it thinks the value needs For example, if you attempt float b;! b = 12.35;! then the compiler will warn you of a possible loss of precision because is regarded as a double If this is really what you want, then you can cast the value float b;! b = (float) 12.35; for literals, there is a quick cast b = 12.35f;!

9 Non-numeric primitive types boolean is used to hold one of the two boolean values true or false! boolean isdone; // declaration! isdone = false;! // assignment! char uses two bytes and holds a Unicode character! char ch;!!// declaration! ch = A ;!!// assignment!

10 Literals Actual values that you type into the source code are called literals - these are things like 100, -23, true, Z, 37, 1e-5, 22, ! Everything in Java has a type, even the literals, so the types of these are respectively!int, int, boolean, char, int, double, int, double!

11 Initialization If a variable is given an initial value directly after it is declared, then you can combine the two steps into one int x;! x = 10;! boolean isfinished;! isfinished = true;! is equivalent to int x = 10;! boolean isfinished = true;!

12 Type-checking The Java compiler does extensive type-checking to make sure that the program does not have any obvious problems The compiler will not allow the wrong type of value to be assigned to a variable int x;! x = true; // cannot assign boolean to int Similarly, the compiler will not allow the wrong type of value to be used as a method or constructor argument What about this? int x = 20;! double y;! y = x;! Although the types don t match perfectly, the computer knows that there is a value of type double corresponding to any value of type int in this case the value 20.0 is assigned to y!

13 Variable declarations Declaring reference types is just the same as for primitive types, with the type occurring before the name String s;! BankAccount b1;! BankAccount b2;! SimpleCanvas sc;! This has created the variables the names for the objects but we have not actually created the objects themselves Creating objects is (almost always) done with the Java keyword new

14 Creating objects To actually create the object, the constructor is called sc = new SimpleCanvas();! b1 = new BankAccount( BillG,12345,10000);! An object is fundamentally different from a primitive value It does not have a fixed size when it is created Its size can change during runtime For this reason, objects are stored in a different part of the computer s memory, and the value that is stored in the variable is a reference to the object A reference contains the information needed to find the actual object in the computer s memory The variable refers to an object (rather than contains an object)

15 References b1! Garbage The variable b1 contains a reference to some location in the heap The actual object that b1 refers to is stored on the heap Some other object The Heap

16 The Golden Rule The behaviour of reference types and primitive types appears quite different, but it all hinges on the following observation A variable of primitive type contains a value A variable of reference type refers to an object The Golden Rule Whenever a variable is used, it is the contents of the shoebox that is used this is the value for a variable of primitive type this is the reference for a variable of reference type

17 Summary Java supplies eight primitive types for the most fundamental pieces of data A variable name and type must be declared before the variable can be used in a program. The Java compiler does extensive type-checking to make sure that the program does not have any obvious problems Creating objects is (almost always) done with the Java keyword new! Every variable has a name used to refer to it Every variable has a value, that changes during program run time.

### EXPRESSIONS AND ASSIGNMENT CITS1001

EXPRESSIONS AND ASSIGNMENT CITS1001 Scope of this lecture Assignment statements Expressions ASSIGNMENT STATEMENT Assignment Statements!!!mark = 50;!! Read as the value in variable on the LHS becomes equal

### Introduction to Programming Using Java (98-388)

Introduction to Programming Using Java (98-388) Understand Java fundamentals Describe the use of main in a Java application Signature of main, why it is static; how to consume an instance of your own class;

### Chapter 2 Using Data. Instructor s Manual Table of Contents. At a Glance. Overview. Objectives. Teaching Tips. Quick Quizzes. Class Discussion Topics

Java Programming, Sixth Edition 2-1 Chapter 2 Using Data At a Glance Instructor s Manual Table of Contents Overview Objectives Teaching Tips Quick Quizzes Class Discussion Topics Additional Projects Additional

### BASIC COMPUTATION. public static void main(string [] args) Fundamentals of Computer Science I

BASIC COMPUTATION x public static void main(string [] args) Fundamentals of Computer Science I Outline Using Eclipse Data Types Variables Primitive and Class Data Types Expressions Declaration Assignment

### Primitive Types. Four integer types: Two floating-point types: One character type: One boolean type: byte short int (most common) long

Primitive Types Four integer types: byte short int (most common) long Two floating-point types: float double (most common) One character type: char One boolean type: boolean 1 2 Primitive Types, cont.

### Full file at

Java Programming, Fifth Edition 2-1 Chapter 2 Using Data within a Program At a Glance Instructor s Manual Table of Contents Overview Objectives Teaching Tips Quick Quizzes Class Discussion Topics Additional

### An Introduction to Processing

An Introduction to Processing Variables, Data Types & Arithmetic Operators Produced by: Dr. Siobhán Drohan Mairead Meagher Department of Computing and Mathematics http://www.wit.ie/ Topics list Variables.

### [0569] p 0318 garbage

A Pointer is a variable which contains the address of another variable. Declaration syntax: Pointer_type *pointer_name; This declaration will create a pointer of the pointer_name which will point to the

### Java Basic Datatypees

Basic Datatypees Variables are nothing but reserved memory locations to store values. This means that when you create a variable you reserve some space in the memory. Based on the data type of a variable,

### Getting started with Java

Getting started with Java Magic Lines public class MagicLines { public static void main(string[] args) { } } Comments Comments are lines in your code that get ignored during execution. Good for leaving

### Programming with Java

Programming with Java Data Types & Input Statement Lecture 04 First stage Software Engineering Dep. Saman M. Omer 2017-2018 Objectives q By the end of this lecture you should be able to : ü Know rules

### Chapter 2: Using Data

Chapter 2: Using Data TRUE/FALSE 1. A variable can hold more than one value at a time. F PTS: 1 REF: 52 2. The legal integer values are -2 31 through 2 31-1. These are the highest and lowest values that

### Exercise: Using Numbers

Exercise: Using Numbers Problem: You are a spy going into an evil party to find the super-secret code phrase (made up of letters and spaces), which you will immediately send via text message to your team

### CPS122 Lecture: From Python to Java last revised January 4, Objectives:

Objectives: CPS122 Lecture: From Python to Java last revised January 4, 2017 1. To introduce the notion of a compiled language 2. To introduce the notions of data type and a statically typed language 3.

Visual C# 2005 2-1 Chapter 2 Using Data At a Glance Instructor s Manual Table of Contents Overview Objectives s Quick Quizzes Class Discussion Topics Additional Projects Additional Resources Key Terms

### printf( Please enter another number: ); scanf( %d, &num2);

CIT 593 Intro to Computer Systems Lecture #13 (11/1/12) Now that we've looked at how an assembly language program runs on a computer, we're ready to move up a level and start working with more powerful

### Java Identifiers, Data Types & Variables

Java Identifiers, Data Types & Variables 1. Java Identifiers: Identifiers are name given to a class, variable or a method. public class TestingShastra { //TestingShastra is an identifier for class char

### CS 231 Data Structures and Algorithms, Fall 2016

CS 231 Data Structures and Algorithms, Fall 2016 Dr. Bruce A. Maxwell Department of Computer Science Colby College Course Description Focuses on the common structures used to store data and the standard

### Pointer Basics. Lecture 13 COP 3014 Spring March 28, 2018

Pointer Basics Lecture 13 COP 3014 Spring 2018 March 28, 2018 What is a Pointer? A pointer is a variable that stores a memory address. Pointers are used to store the addresses of other variables or memory

### data_type variable_name = value; Here value is optional because in java, you can declare the variable first and then later assign the value to it.

Introduction to JAVA JAVA is a programming language which is used in Android App Development. It is class based and object oriented programming whose syntax is influenced by C++. The primary goals of JAVA

CS313D: ADVANCED PROGRAMMING LANGUAGE Computer Science department Lecture 2 : C# Language Basics Lecture Contents 2 The C# language First program Variables and constants Input/output Expressions and casting

### CS112 Lecture: Primitive Types, Operators, Strings

CS112 Lecture: Primitive Types, Operators, Strings Last revised 1/24/06 Objectives: 1. To explain the fundamental distinction between primitive types and reference types, and to introduce the Java primitive

### int[] a; a = new int[8]; a[0] = 1; a[1] = 1; for (int i = 2; i < 8; i++) a[i] = a[i-1] - a[i-2];

1. The source code for a class (a) must explicitly define exactly one constructor. (b) can explicitly define zero, one or more constructors. (c) must explicitly define at least one constructor. (d) can

### Datatypes, Variables, and Operations

Datatypes, Variables, and Operations 1 Primitive Type Classification 2 Numerical Data Types Name Range Storage Size byte 2 7 to 2 7 1 (-128 to 127) 8-bit signed short 2 15 to 2 15 1 (-32768 to 32767) 16-bit

### Data Types, Variables and Arrays. OOC 4 th Sem, B Div Prof. Mouna M. Naravani

Data Types, Variables and Arrays OOC 4 th Sem, B Div 2016-17 Prof. Mouna M. Naravani Identifiers in Java Identifiers are the names of variables, methods, classes, packages and interfaces. Identifiers must

### Introduction. Primitive Data Types: Integer. Primitive Data Types. ICOM 4036 Programming Languages

ICOM 4036 Programming Languages Primitive Data Types Character String Types User-Defined Ordinal Types Array Types Associative Arrays Record Types Union Types Pointer and Reference Types Data Types This

### PROGRAMMING FUNDAMENTALS

PROGRAMMING FUNDAMENTALS Q1. Name any two Object Oriented Programming languages? Q2. Why is java called a platform independent language? Q3. Elaborate the java Compilation process. Q4. Why do we write

### Review for Test 1 (Chapter 1-5)

Review for Test 1 (Chapter 1-5) 1. Introduction to Computers, Programs, and Java a) What is a computer? b) What is a computer program? c) A bit is a binary digit 0 or 1. A byte is a sequence of 8 bits.

### Fall 2017 CISC124 9/16/2017

CISC124 Labs start this week in JEFF 155: Meet your TA. Check out the course web site, if you have not already done so. Watch lecture videos if you need to review anything we have already done. Problems

### 1 class Lecture2 { 2 3 "Elementray Programming" / References 8 [1] Ch. 2 in YDL 9 [2] Ch. 2 and 3 in Sharan 10 [3] Ch.

1 class Lecture2 { 2 3 "Elementray Programming" 4 5 } 6 7 / References 8 [1] Ch. 2 in YDL 9 [2] Ch. 2 and 3 in Sharan 10 [3] Ch. 2 in HS 11 / Zheng-Liang Lu Java Programming 41 / 68 Example Given the radius

### Exercise: Inventing Language

Memory Computers get their powerful flexibility from the ability to store and retrieve data Data is stored in main memory, also known as Random Access Memory (RAM) Exercise: Inventing Language Get a separate

### 1 Epic Test Review 2 Epic Test Review 3 Epic Test Review 4. Epic Test Review 5 Epic Test Review 6 Epic Test Review 7 Epic Test Review 8

Epic Test Review 1 Epic Test Review 2 Epic Test Review 3 Epic Test Review 4 Write a line of code that outputs the phase Hello World to the console without creating a new line character. System.out.print(

### Control Structures. Lecture 4 COP 3014 Fall September 18, 2017

Control Structures Lecture 4 COP 3014 Fall 2017 September 18, 2017 Control Flow Control flow refers to the specification of the order in which the individual statements, instructions or function calls

### CHAPTER 7 OBJECTS AND CLASSES

CHAPTER 7 OBJECTS AND CLASSES OBJECTIVES After completing Objects and Classes, you will be able to: Explain the use of classes in Java for representing structured data. Distinguish between objects and

### Zheng-Liang Lu Java Programming 45 / 79

1 class Lecture2 { 2 3 "Elementray Programming" 4 5 } 6 7 / References 8 [1] Ch. 2 in YDL 9 [2] Ch. 2 and 3 in Sharan 10 [3] Ch. 2 in HS 11 / Zheng-Liang Lu Java Programming 45 / 79 Example Given a radius

### COMP 250: Java Programming I. Carlos G. Oliver, Jérôme Waldispühl January 17-18, 2018 Slides adapted from M. Blanchette

COMP 250: Java Programming I Carlos G. Oliver, Jérôme Waldispühl January 17-18, 2018 Slides adapted from M. Blanchette Variables and types [Downey Ch 2] Variable: temporary storage location in memory.

### Full file at

Java Programming: From Problem Analysis to Program Design, 3 rd Edition 2-1 Chapter 2 Basic Elements of Java At a Glance Instructor s Manual Table of Contents Overview Objectives s Quick Quizzes Class

### LECTURE 3 C++ Basics Part 2

LECTURE 3 C++ Basics Part 2 OVERVIEW Operators Type Conversions OPERATORS Operators are special built-in symbols that have functionality, and work on operands. Operators are actually functions that use

### Computational Expression

Computational Expression Variables, Primitive Data Types, Expressions Janyl Jumadinova 28-30 January, 2019 Janyl Jumadinova Computational Expression 28-30 January, 2019 1 / 17 Variables Variable is a name

### Control Structures in Java if-else and switch

Control Structures in Java if-else and switch Lecture 4 CGS 3416 Spring 2016 February 2, 2016 Control Flow Control flow refers to the specification of the order in which the individual statements, instructions

### 2/12/17. Goals of this Lecture. Historical context Princeton University Computer Science 217: Introduction to Programming Systems

Princeton University Computer Science 217: Introduction to Programming Systems The C Programming Language Part 1 For Your Amusement C is quirky, flawed, and an enormous success. While accidents of history

### CIS133J. Working with Numbers in Java

CIS133J Working with Numbers in Java Contents: Using variables with integral numbers Using variables with floating point numbers How to declare integral variables How to declare floating point variables

### 3. Simple Types, Variables, and Constants

3. Simple Types, Variables, and Constants This section of the lectures will look at simple containers in which you can storing single values in the programming language C++. You might find it interesting

### C++ Data Types. 1 Simple C++ Data Types 2. 3 Numeric Types Integers (whole numbers) Decimal Numbers... 5

C++ Data Types Contents 1 Simple C++ Data Types 2 2 Quick Note About Representations 3 3 Numeric Types 4 3.1 Integers (whole numbers)............................................ 4 3.2 Decimal Numbers.................................................

### Lexical Structure (Chapter 3, JLS)

Lecture Notes CS 140 Winter 2006 Craig A. Rich Lexical Structure (Chapter 3, JLS) - A Java source code file is viewed as a string of unicode characters, including line separators. - A Java source code

### QUIZ. What is wrong with this code that uses default arguments?

QUIZ What is wrong with this code that uses default arguments? Solution The value of the default argument should be placed in either declaration or definition, not both! QUIZ What is wrong with this code

### Princeton University Computer Science 217: Introduction to Programming Systems The C Programming Language Part 1

Princeton University Computer Science 217: Introduction to Programming Systems The C Programming Language Part 1 C is quirky, flawed, and an enormous success. While accidents of history surely helped,

### Introduction to C++ with content from

Introduction to C++ with content from www.cplusplus.com 2 Introduction C++ widely-used general-purpose programming language procedural and object-oriented support strong support created by Bjarne Stroustrup

### Java Fall 2018 Margaret Reid-Miller

Java 15-121 Fall 2018 Margaret Reid-Miller Reminders How many late days can you use all semester? 3 How many late days can you use for a single assignment? 1 What is the penalty for turning an assignment

### Defining Classes. Chap 1 introduced many concepts informally, in this chapter we will be more formal in defining

Defining Classes Chap 1 introduced many concepts informally, in this chapter we will be more formal in defining Classes, fields, and constructors Methods and parameters, mutators and accessors Assignment

### Chapter 2: Using Data

Chapter 2: Using Data TRUE/FALSE 1. A variable can hold more than one value at a time. F PTS: 1 REF: 52 2. The legal integer values are -2 31 through 2 31-1. These are the highest and lowest values that

### The type of all data used in a C (or C++) program must be specified

The type of all data used in a C (or C++) program must be specified A data type is a description of the data being represented That is, a set of possible values and a set of operations on those values

### CPS122 Lecture: From Python to Java

Objectives: CPS122 Lecture: From Python to Java last revised January 7, 2013 1. To introduce the notion of a compiled language 2. To introduce the notions of data type and a statically typed language 3.

### Assumptions. History

Assumptions A Brief Introduction to Java for C++ Programmers: Part 1 ENGI 5895: Software Design Faculty of Engineering & Applied Science Memorial University of Newfoundland You already know C++ You understand

### Pointers (continued), arrays and strings

Pointers (continued), arrays and strings 1 Last week We have seen pointers, e.g. of type char *p with the operators * and & These are tricky to understand, unless you draw pictures 2 Pointer arithmetic

### Variables. Data Types.

Variables. Data Types. The usefulness of the "Hello World" programs shown in the previous section is quite questionable. We had to write several lines of code, compile them, and then execute the resulting

### COMP-202: Foundations of Programming

COMP-202: Foundations of Programming Lecture 3: Basic data types Jackie Cheung, Winter 2016 Review: Hello World public class HelloWorld { } public static void main(string[] args) { } System.out.println("Hello,

### CHAPTER 7 OBJECTS AND CLASSES

CHAPTER 7 OBJECTS AND CLASSES OBJECTIVES After completing Objects and Classes, you will be able to: Explain the use of classes in Java for representing structured data. Distinguish between objects and

### Basic Operations jgrasp debugger Writing Programs & Checkstyle

Basic Operations jgrasp debugger Writing Programs & Checkstyle Suppose you wanted to write a computer game to play "Rock, Paper, Scissors". How many combinations are there? Is there a tricky way to represent

### Understand Computer Storage and Data Types

Understand Computer Storage and Data Types Lesson Overview Students will understand computer storage and data types. In this lesson, you will learn: How a computer stores programs and instructions in computer

### A brief introduction to C programming for Java programmers

A brief introduction to C programming for Java programmers Sven Gestegård Robertz September 2017 There are many similarities between Java and C. The syntax in Java is basically

### CS321 Languages and Compiler Design I. Winter 2012 Lecture 2

CS321 Languages and Compiler Design I Winter 2012 Lecture 2 1 A (RE-)INTRODUCTION TO JAVA FOR C++/C PROGRAMMERS Why Java? Developed by Sun Microsystems (now Oracle) beginning in 1995. Conceived as a better,

### CS5000: Foundations of Programming. Mingon Kang, PhD Computer Science, Kennesaw State University

CS5000: Foundations of Programming Mingon Kang, PhD Computer Science, Kennesaw State University Overview of Source Code Components Comments Library declaration Classes Functions Variables Comments Can

### Basics of Java Programming

Basics of Java Programming Lecture 2 COP 3252 Summer 2017 May 16, 2017 Components of a Java Program statements - A statement is some action or sequence of actions, given as a command in code. A statement

### University of Technology. Laser & Optoelectronics Engineering Department. C++ Lab.

University of Technology Laser & Optoelectronics Engineering Department C++ Lab. Second week Variables Data Types. The usefulness of the "Hello World" programs shown in the previous section is quite questionable.

### 1007 Imperative Programming Part II

Agenda 1007 Imperative Programming Part II We ve seen the basic ideas of sequence, iteration and selection. Now let s look at what else we need to start writing useful programs. Details now start to be

### Peer Instruction 1. Elementary Programming

Peer Instruction 1 Elementary Programming 0 Which of the following variable declarations will not compile? Please select the single correct answer. A. int i = 778899; B. double x = 5.43212345; C. char

### Values, Variables, Types & Arithmetic Expressions. Agenda

Values, Variables, Types & Arithmetic Expressions Lecture 2 Object-Oriented Programming Agenda Inside of a Computer Value Variable Data Types in Java Literals Identifiers Type conversions Manipulating

### COE318 Lecture Notes Week 3 (Week of Sept 17, 2012)

COE318 Lecture Notes: Week 3 1 of 8 COE318 Lecture Notes Week 3 (Week of Sept 17, 2012) Announcements Quiz (5% of total mark) on Wednesday, September 26, 2012. Covers weeks 1 3. This includes both the

### Unit 2: Java in the small. Prepared by: Dr. Abdallah Mohamed, AOU-KW

Unit 2: Java in the small Prepared by: Dr. Abdallah Mohamed, AOU-KW 1 Unit 2: Java in the small Introduction The previous unit introduced the idea of objects communicating through the invocation of methods

### index.pdf January 21,

index.pdf January 21, 2013 1 ITI 1121. Introduction to Computing II Circle Let s complete the implementation of the class Circle. Marcel Turcotte School of Electrical Engineering and Computer Science Version

### Pointers (continued), arrays and strings

Pointers (continued), arrays and strings 1 Last week We have seen pointers, e.g. of type char *p with the operators * and & These are tricky to understand, unless you draw pictures 2 Pointer arithmetic

### CS-140 Fall 2017 Test 1 Version Practice Practie for Sept. 27, Name:

CS-140 Fall 2017 Test 1 Version Practice Practie for Sept. 27, 2017 Name: 1. (10 points) For the following, Check T if the statement is true, the F if the statement is false. (a) T F : In mathematics,

### false, import, new 1 class Lecture2 { 2 3 "Data types, Variables, and Operators" 4

1 class Lecture2 { 2 3 "Data types, Variables, and Operators" 4 5 } 6 7 // Keywords: 8 byte, short, int, long, char, float, double, boolean, true, false, import, new Zheng-Liang Lu Java Programming 44

### COSC 2P91. Introduction Part Deux. Week 1b. Brock University. Brock University (Week 1b) Introduction Part Deux 1 / 14

COSC 2P91 Introduction Part Deux Week 1b Brock University Brock University (Week 1b) Introduction Part Deux 1 / 14 Source Files Like most other compiled languages, we ll be dealing with a few different

### Data and Variables. Data Types Expressions. String Concatenation Variables Declaration Assignment Shorthand operators. Operators Precedence

Data and Variables Data Types Expressions Operators Precedence String Concatenation Variables Declaration Assignment Shorthand operators Review class All code in a java file is written in a class public

### Chapter 2 Using Data. Instructor s Manual Table of Contents. At a Glance. A Guide to this Instructor s Manual:

Java Programming, Eighth Edition 2-1 Chapter 2 Using Data A Guide to this Instructor s Manual: We have designed this Instructor s Manual to supplement and enhance your teaching experience through classroom

### Introduction to Computer Science and Object-Oriented Programming

COMP 111 Introduction to Computer Science and Object-Oriented Programming Values Judgment Programs Manipulate Values Inputs them Stores them Calculates new values from existing ones Outputs them In Java

### false, import, new 1 class Lecture2 { 2 3 "Data types, Variables, and Operators" 4

1 class Lecture2 { 2 3 "Data types, Variables, and Operators" 4 5 } 6 7 // Keywords: 8 byte, short, int, long, char, float, double, boolean, true, false, import, new Zheng-Liang Lu Java Programming 44

### CS260 Intro to Java & Android 03.Java Language Basics

03.Java Language Basics http://www.tutorialspoint.com/java/index.htm CS260 - Intro to Java & Android 1 What is the distinction between fields and variables? Java has the following kinds of variables: Instance

### Lecture 2 Tao Wang 1

Lecture 2 Tao Wang 1 Objectives In this chapter, you will learn about: Modular programs Programming style Data types Arithmetic operations Variables and declaration statements Common programming errors

### Chapter 02: Using Data

True / False 1. A variable can hold more than one value at a time. ANSWER: False REFERENCES: 54 2. The int data type is the most commonly used integer type. ANSWER: True REFERENCES: 64 3. Multiplication,

### Declaration and Memory

Declaration and Memory With the declaration int width; the compiler will set aside a 4-byte (32-bit) block of memory (see right) The compiler has a symbol table, which will have an entry such as Identifier

### ITI Introduction to Computing II

ITI 1121. Introduction to Computing II Marcel Turcotte School of Electrical Engineering and Computer Science Inheritance (part II) Polymorphism Version of January 21, 2013 Abstract These lecture notes

### The Arithmetic Operators. Unary Operators. Relational Operators. Examples of use of ++ and

The Arithmetic Operators The arithmetic operators refer to the standard mathematical operators: addition, subtraction, multiplication, division and modulus. Op. Use Description + x + y adds x and y x y

### The Arithmetic Operators

The Arithmetic Operators The arithmetic operators refer to the standard mathematical operators: addition, subtraction, multiplication, division and modulus. Examples: Op. Use Description + x + y adds x

### Unit 2: Java in the small

Prepared by: Dr. Abdallah Mohamed, AOU-KW 1 Introduction The previous unit introduced the idea of objects communicating through the invocation of methods on objects. In this unit you will learn: how to

### ITI Introduction to Computing II

ITI 1121. Introduction to Computing II Marcel Turcotte School of Electrical Engineering and Computer Science Inheritance (part II) Polymorphism Version of January 21, 2013 Abstract These lecture notes

### CSc Introduction to Computing

CSc 10200 Introduction to Computing Lecture 2 Edgardo Molina Fall 2011 - City College of New York Thursday, September 1, 2011 Introduction to C++ Modular program: A program consisting of interrelated segments

Java How to Program, 10/e Education, Inc. All Rights Reserved. Each class you create becomes a new type that can be used to declare variables and create objects. You can declare new classes as needed;

### Object oriented programming. Instructor: Masoud Asghari Web page: Ch: 3

Object oriented programming Instructor: Masoud Asghari Web page: http://www.masses.ir/lectures/oops2017sut Ch: 3 1 In this slide We follow: https://docs.oracle.com/javase/tutorial/index.html Trail: Learning

### TOPIC 2 INTRODUCTION TO JAVA AND DR JAVA

1 TOPIC 2 INTRODUCTION TO JAVA AND DR JAVA Notes adapted from Introduction to Computing and Programming with Java: A Multimedia Approach by M. Guzdial and B. Ericson, and instructor materials prepared

### CS242 COMPUTER PROGRAMMING

CS242 COMPUTER PROGRAMMING I.Safa a Alawneh Variables Outline 2 Data Type C++ Built-in Data Types o o o o bool Data Type char Data Type int Data Type Floating-Point Data Types Variable Declaration Initializing

### Ticket Machine Project(s)

Ticket Machine Project(s) Understanding the basic contents of classes Produced by: Dr. Siobhán Drohan (based on Chapter 2, Objects First with Java - A Practical Introduction using BlueJ, David J. Barnes,

### false, import, new 1 class Lecture2 { 2 3 "Data types, Variables, and Operators" 4

1 class Lecture2 { 2 3 "Data types, Variables, and Operators" 4 5 } 6 7 // Keywords: 8 byte, short, int, long, char, float, double, boolean, true, false, import, new Zheng-Liang Lu Java Programming 44

### int a; int b = 3; for (a = 0; a < 8 b < 20; a++) {a = a + b; b = b + a;}

1. What does mystery(3) return? public int mystery (int n) { int m = 0; while (n > 1) {if (n % 2 == 0) n = n / 2; else n = 3 * n + 1; m = m + 1;} return m; } (a) 0 (b) 1 (c) 6 (d) (*) 7 (e) 8 2. What are

### Values and Variables 1 / 30

Values and Variables 1 / 30 Values 2 / 30 Computing Computing is any purposeful activity that marries the representation of some dynamic domain with the representation of some dynamic machine that provides

### Basic data types. Building blocks of computation

Basic data types Building blocks of computation Goals By the end of this lesson you will be able to: Understand the commonly used basic data types of C++ including Characters Integers Floating-point values