Getting started with C++ - Quiz Explanation
The correct answers are indicated below, along with text that explains the correct answers.
1.
In C++, the token//
is used for:
A.
integer division
B.
concatenation
C.
comments
D.
exponentiation
The correct answer is C.
It is the rest-of-line comment symbol.
2.
The function strlen()
computes:
A.
the number of non-whitespace characters in a string
B.
the length of a string, not including the null terminator
C.
the number of alphabetical characters in a string
D.
the length of a string, including the null terminator
The correct answer is B.
It is the standard library function for the length of a null-terminated string. The function strlen() returns the length of the string, not including the null terminator.
3.
In C++, cout
is found in which library file?
A.
ctype.h
B.
stdlib.h
C.
math.h
D.
iostream.h
The correct answer is D.
The standard C++ library iostream.h contains the variable cout.
4.
One difference between C++ and C is that C++:
A.
has long double
B.
is block structured
C.
has declarations that can go after executable code
D.
has no do-while statement
The correct answer is C.
Declarations in C++ can go most anywhere in executable code, but in C they must be at the head of blocks.
5.
Assume that before the following cast, i
is type int. What will i be after the cast is performed?
y = static_cast<float>(i);
A.
float
B.
char
C.
int
D.
double
The correct answer is C.
A static_cast does not change the type of the variable being cast.
6.
The standard identifier cin
is used for:
A.
a compiler flag
B.
standard output
C.
standard input
D.
the integer -1
The correct answer is C.
The variable cin is used for standard input. The variable cout is for standard output.
7.
In enum names {Harold, Phillip, Ira, Morris}
the enumerator Morris is the integer value constant:
A.
4
B.
3
C.
5
D.
system dependent
The correct answer is B.
Harold is by default the constant 0, Phillip 1, Ira 2, and Morris is, therefore, 3.
8.
The keyword endl
:
A.
defines a symbolic constant
B.
specifies that a function is to be compiled, if possible, as inline code
C.
provides assertion testing
D.
flushes the output stream and adds a new line
The correct answer is D.
The keyword endl is a
manipulator,
which causes the output stream to be flushed and a new line to be added. To define a symbolic constant or named literal, use the const keyword. To specify that a function be compiled as inline code, use the inline keyword. Assertion testing is provided in C++ by using the assert.h library.