Programming Fundamentals PDF

Programming Fundamentals Dr. Mustafa © Copyright 2017 by Pearson Education, Ltd. All Rights Reserved.  We have studied  Algorithms  Flowcharts  Software development life cycle  Simple C++ program © Copyright 2017 by Pearson...

Programming Fundamentals Dr. Mustafa © Copyright 2017 by Pearson Education, Ltd. All Rights Reserved.  We have studied  Algorithms  Flowcharts  Software development life cycle  Simple C++ program © Copyright 2017 by Pearson Education, Ltd. All Rights Reserved. © Copyright 2017 by Pearson Education, Ltd. All Rights Reserved.  A single statement can print multiple lines by using newline characters.  Each time the \n (newline) escape sequence is encountered in the output stream, the screen cursor is positioned to the beginning of the next line.  To get a blank line in your output, place two newline characters back to back. © Copyright 2017 by Pearson Education, Ltd. All Rights Reserved.  The next program obtains two integers typed by a user at the keyboard, computes their sum and outputs the result using std::cout.  Figure 2.5 shows the program and sample inputs and outputs. © Copyright 2017 by Pearson Education, Ltd. All Rights Reserved.  Data type double is for specifying real numbers, and data type char for specifying character data.  Real numbers are numbers with decimal points, such as 3.4, 0.0 and –11.19.  A char variable may hold only a single lowercase letter, a single uppercase letter, a single digit or a single special character (e.g., $ or *).  Types such as int, double and char are called fundamental types.  Fundamental-type names are keywords and therefore must appear in all lowercase letters.  Appendix C contains the complete list of fundamental types. © Copyright 2017 by Pearson Education, Ltd. All Rights Reserved.  A variable name is any valid identifier that is not a keyword.  An identifier is a series of characters consisting of letters, digits and underscores ( _ ) that does not begin with a digit.  C++ is case sensitive—uppercase and lowercase letters are different, so a1 and A1 are different identifiers. © Copyright 2017 by Pearson Education, Ltd. All Rights Reserved.  Declarations of variables can be placed almost anywhere in a program, but they must appear before their corresponding variables are used in the program. © Copyright 2017 by Pearson Education, Ltd. All Rights Reserved.  A prompt it directs the user to take a specific action.  A cin statement uses the input stream object cin (of namespace std) and the stream extraction operator, >>, to obtain a value from the keyboard.  Using the stream extraction operator with std::cin takes character input from the standard input stream, which is usually the keyboard. © Copyright 2017 by Pearson Education, Ltd. All Rights Reserved.  When the computer executes an input statement that places a value in an int variable, it waits for the user to enter a value for variable number1.  The user responds by typing the number (as characters) then pressing the Enter key (sometimes called the Return key) to send the characters to the computer.  The computer converts the character representation of the number to an integer and assigns (i.e., copies) this number (or value) to the variable number1.  Any subsequent references to number1 in this program will use this same value.  Pressing Enter also causes the cursor to move to the beginning of the next line on the screen. © Copyright 2017 by Pearson Education, Ltd. All Rights Reserved.  In this program, an assignment statement adds the values of variables number1 and number2 and assigns the result to variable sum using the assignment operator =. ◦ Most calculations are performed in assignment statements.  The = operator and the + operator are called binary operators because each has two operands. © Copyright 2017 by Pearson Education, Ltd. All Rights Reserved.  std::endl is a so-called stream manipulator.  The name endl is an abbreviation for “end line” and belongs to namespace std.  The std::endl stream manipulator outputs a newline, then “flushes the output buffer.” ◦ This simply means that, on some systems where outputs accumulate in the machine until there are enough to “make it worthwhile” to display them on the screen, std::endl forces any accumulated outputs to be displayed at that moment. ◦ This can be important when the outputs are prompting the user for an action, such as entering data. © Copyright 2017 by Pearson Education, Ltd. All Rights Reserved.  Using multiple stream insertion operators (