c++ fundamentals, conditionals, loops, functions - tutorial 8 · c++ fundamentals, conditionals,...

C++ Fundamentals, Conditionals, Loops,

FunctionsTutorial 8

Akhil Krishnan

Department of Computing and SoftwareMcMaster University

Akhil Krishnan (Department of Computing and Software McMaster University)C++ Fundamentals, Conditionals, Loops, Functions 1 / 28

Outline

1 Getting EclipseInstalling EclipseA Simple Program

2 ExerciseSolution

3 Java to C++ TransitionArithmetic OperationsInput OutputStringsFilesArraysObjects Creation


Getting Eclipse Installing Eclipse

Install Eclipse for C++

Download link:https://eclipse.org/downloads/


https://eclipse.org/downloads/


Installing Eclipse on a Mac

Mac

1 Find .tar.gz file (probably in your Downloads folder)2 Drag it to the Desktop3 Double-click on it and find a folder named “eclipse”4 Drag “eclipse” folder into Applications folder5 Inside “eclipse” folder find application named “Eclipse”6 Drag it to your dock to make it easier to launch



Installing Eclipse on a PC

Windows

1 Find .zip file (probably in your Downloads folder)2 Right-click on it3 Select “Extract All. . . ” and extract to “C:” (or whatever your

root drive is)4 After it is extracted, drag “eclipse.exe” to your Start menu to

make it easier to launch


Getting Eclipse A Simple Program

A Simple Program

Choose the Work space location. Choose a di↵erent Work spacelocation from Java workspace so that you can use themsimultaneously.To create a New Project, select File ! New ! C++ Projectand choose the following option in the Wizard.



A Simple Program

To create a new source file, select File ! New ! Source File.Then a New Window opens as shown below.



A Simple Program

Type the following code and save the file. Then Build Project asshown belowThen run the program as shown below.



A Simple Program

The File Header is automatically populated with details likeAuthor name, Date Created On and the name of the File

Then run the program as shown below.



Preferences

Go to Eclipse ! Preferences... ! C\C++ ! New C\C++Project Wizard

In ToolChains, click on MacOSX GCC and then select ”MakeToolChains Preferred” and select OK.


Exercise Solution

Exercise: Try this ...

Write a C++ program to find prime numbers between givenrange of numbers


Exercise Solution

Solution

1 #include <iostream >

2 #include <math.h>

3 using namespace std;

4 int main()

5 {

6 int startNum ,endNum;

7 int found=0,count =0;

8 cout <<"Enter Number START of Range: ";

9 cin >>startNum;

10 cout <<"Enter Number END of Range: ";

11 cin >>endNum;

12 for(int i=startNum;i<= endNum;i++)

13 {

14 for(int j=2;j<=sqrt(i);j++)

15 {

16 if(i%j==0)

17 count ++;


Exercise Solution

Continued...

1 }

2 if(count ==0&&i!=1)

3 { found ++;

4 cout <<"Prime Number -> "<<i<<endl;

5 count =0;

6 }

7 count =0;

8 }

910 cout <<"Total Prime Number Between Range "<<startNum <<

" to "<<endNum <<" = "<<found <<endl;

11 return 1;

12 }


Exercise Solution

Output


Java to C++ Transition Arithmetic Operations

Java Vs C++: Arithmetic Operations


Java to C++ Transition Arithmetic Operations

Java Vs C++: Arithmetic Operations

Constants

To create a constant value in Java requires the notation of staticfinal before the variable declaration. Note that the constantMAX in C++ uses, the much simpler and more direct constkeyword.

Boolean

C++ does not type check the values you provide to ifstatements, while loops or for loops. You can make mistakes andC++ will not warn you in places where Java would report anerror.

Output

Note that in Java a complex line of output is assembled using +to concatenate strings together. In C++ this is done using thehh operator.


Java to C++ Transition Input Output

Java Vs C++: Input Output


Java to C++ Transition Input Output

Java Vs C++: Input Output

Importing

In Java, the easiest way to access input from the keyboard isthrough the Scanner class. This is imported at Main.java.Similarly in C++ we include the iostream file

Input source

In Java we get input from the keyboard via System.in. Weconnect this to a scanner as shown at Main.java. In C++ this issimpler. We access keyboard input from the variable cin, whichwas declared inside of iostream.

Reading input

To read in an integer in Java we used the nextInt() methodshown at Main.java. To do the same thing in C++ we use theii operator as shown at Main.cpp


Java to C++ Transition Strings

Java Vs C++: Strings


Java to C++ Transition Strings

Java Vs C++: Strings

string

To work with strings in Java we simply use the String classdirectly. The String class is automatically imported. In C++ thestring class is not capitalized and is not automatically imported.We must include its declarations as in C++.Java uses String butC++ uses string.

Relational Operators

In C++ the relational operator can be used to comparestrings.This is because in C++ strings are stored as ASCIIcharacters.


Java to C++ Transition Files

Java Vs C++: Files


Java to C++ Transition Files

Java Vs C++: Files

Include files

In C++ if we are going to read and write with files we need toinclude iostream and fstream at Main.cpp

Opening a file for output

In Java there are three steps needed to open a file for writing: 1)specifying the file name and output stream, 2) wrapping theoutput stream with a PrintStream so that the nice methods areavailable and 3) catching an exception for any errors. In C++there is only the opening of the output file and an if statementto catch any errors. In Java we specify the file name(”data.txt”) by including it in a FileOutputStream constructor.In C++ we use the open() method as at Main.cpp. If there is anerror in opening a file, Java with raise an exception. This mustbe caught in order to handle the error.


Java to C++ Transition Arrays

Java Vs C++: Arrays

Java:You can create an array by using the new operator with thefollowing syntax:

dataType[] arrayRefVar = new dataType[arraySize];

Ex:int [] a=new int[4];

C++To declare an array in C++, specify the type of the elementsand the number of elements required by an array as follows:

type arrayName [ arraySize ];

Ex:int a[4];


Java to C++ Transition Objects Creation

Java Vs C++: Objects Creation

1 class Abc

2 { ...

3 }

Java:You can create an object by using the new operator with thefollowing syntax:

Class name obj reference= new Class();Ex: Abc a= new Abc();C++To declare an array in C++, specify the type of the elementsand the number of elements required by an array as follows:Classname obj reference;Ex: Abc a;



C++ Some Additional Features

Pointers

Destructors

Operator Overloading

Multiple Inheritance

Struct,Enum and Union

Supports Goto Statement



The End


c++ fundamentals, conditionals, loops, functions - tutorial 8 · c++ fundamentals, conditionals,...

Documents