Post on 13-Jan-2016
Instructor - C. BoyleInstructor - C. Boyle Fall Semester - 2015 Fall Semester - 2015 cboyle@cs.odu.educboyle@cs.odu.edu
This was an in-class exercise, and something may have changed, SO
Do not count on the accuracy of the solutions in this presentation!
Verify With Your Textbook!
Look Up The Answers Yourself!
Q#1 Question
Which of the following methods for inserting comments in a C++ program are valid?
Answer
• \\ comments in your program
• \* comments in your program *\
• /* comments in your program */
• #comments in your program
Q#1-Solution
There are two methods for inserting comments in a C++ program: a comment can begin with the characters // or a comment can begin with the characters /* and then end with the characters */
Q#2 Question
Question • True or False: The setw manipulator cannot use a
string as an argument.
Answer• True• False
Q#3 Question
Consider the following preprocessor directive:
#include <iostream.h>The directive specifies that the statements in the file:
ANSWER • contains a constant we use in executing loops. • contains information related to the input statement used in
the program • contains info related to functions used to compute the sum of
a value. • contains a comment we use in exiting the program.
Q#4 Question
Multiple Answer Question
The main function contains two types of statements:
Answer• statements that define memory locations which will be used
in the program • pre-processor statements that define additional code to be
inserted.• statements that specify actions to be taken. • post-processor statements that define additional code to
executed.
Q#5 Question
Question True or False: The if…else statement is a one-way selection structure.
Answer
• True
• False
Q#6 Question
Multiple Answer Question
//define and initialize variables
double quizscore1, quizscore3, quiz4=10, averagescore=4.0, avg, sumscores;
This statement specifies that
Answer• the program will use five variables.• the variable quiz4 should be initialized to the value of 10.0.• the variable average should be initialized to the value of 10.0.• nothing, because it should all be on one line.
Q#7 Question
Question Rules for selecting a valid identifier are:
Answer
• An identifier cannot begin with an alphabetic character or the
underscore character.• Alphabetic characters in an identifier must be lower case
letters. • An identifier can be of any length. • Alphabetic characters in an identifier can be lower case or
upper case letters.
Q#8 Question
Question The following is a valid identifier:
1_quiz
Answer
• True
• False
Q#9 Question
Question The following is a valid identifier:
max-value
Answer
• True
• False
Q#10 Question
Question The following is a valid identifier:
$uperMan
Answer
• True
• False
Q#11 Question
Question True or False: File stream variables are predefined in the fstream header file and associated with input/output sources.
Answer
• True
• False
Q#12 Question
Question C++ is case sensitive, that is, it distinguishes upper case letters from lowercase letters. Thus Sum, sum, and SUM represent three ways of safely working with the same variable value.
Answer
• True
• False
Q#13 Question
Question
The difference between the float, double, and long double types relates to the
Answer• exponent (or accuracy) and length of the values represented. • precision (or accuracy) and range of the values represented. • exponent (short accuracy), range (long accuracy) and length
of the values represented. • precision (or accuracy) and range of the libraries included.
Q#14 Question
Question A float value will have a wider range of values for exponents than a double value.
Answer
• True
• False
Q#15 Question
Multiple Answer Question Select the true statements, concerning symbolic constants:
Answer• The compiler will replace each occurrence of the constant
identifier with the constant value. • Constant declarations, like variable declarations, and with a
colon. (:)
• Several symbolic constants can be declared in one statement if they have the same data type.
• A symbolic constants is declared by prefixing a declaration with the const specifier.
Q#16 Question
Question
The assignment statements below define and initialize the variables at the same time.
double sum, total;
total = 10;
sum = total;
Answer• True• False
Q#17 Question
Question • Multiple assignments are allowed in C++, as in
the following statement, which assigns a value of zero to each of the variables x,y, and z.
x = y = z = 0;
Answer
• True
• False
Q#18 Question
Question What is an enumeration type?
Answer• C++’s method for allowing programmers to create
their own simple data types. • C++’s method for allowing programmers to use
numerals to update control structures.• One of C++’s simple integer data types, such as int.• C++’s library of available numerical variables.
Q#19 Question
Question An expression that has operands of different data types is called a(n)
Answer
• mixed expression
• homogenous expression
• simple
• enumerated expression
Q#20 Question
Question What is the syntax for declaring single or multiple variables?
Answer• dataType identifier, identifier, …; • variableName dataType identifier, identifier, …; • dataName identifierType, identifierType, …; • identifier, identifier, …;
Q#21 Question
Question True or False: The semantic rules of a language tell you what is legal and what is not legal.
Answer
• True
• False
Q#22 Question
Question What is the syntax of the ignore function?
Answer
• cin.ignore(intExp, chExp);
• cout<< stringName.ignore(intExp, intExp);
• cin>> stringName.ignore(intExp, intExp);
• int value.stringName.ignore(intExp, intExp);
Q#23 Question
Question The header file ______________ needs to be included to use the setw function.
Answer
• iomanip
• iostream
• iosetw
• cmath
Q#24 Question
Question Which of the following would you use as a statement to format the output of decimal numbers to two decimal places?
Answer
• cout << setprecision(2);
• cin << setprecision(2);
• cout << setdotwidth( );
• cout >> setw.setprecision(2);
Q#25 Question
Question Which of the following are true?
Answer
• The if…else statement is a two-way selection structure.
• A unary operator takes three operands.
• The equality operator in C++ is =
• A relational operator allows you to make comparisons in a program.
QUESTIONS?QUESTIONS?
Assignments:Assignments:
Quiz due before class on TuesdayQuiz due before class on Tuesday