Deck 21: Class String and String Stream Processing

Question 1

Which function changes the actual string stored in the string object (i.e., is not a const member function)?

A) length
B) empty
C) capacity
D) resize

Answer 1

D

Question 2

What type of value is returned by the overloaded equality and relational operators for strings?

A) int
B) bool
C) double
D) null

Answer 2

B

Question 3

Iterators do not:

A) Allow the characters to be modified.
B) Allow backward traversal of strings.
C) Have range checking.
D) Have syntax similar to pointer operations.

Answer 3

C

Question 4

Which of the following is an invalid definition?

A) string sa = "computers";
B) string sb{"computers"};
C) string sc{'c'};
D) string sd{9, 'c'};

Question 5

Which of the following searches through a string object from right-to-left?

A) find
B) find_first_of
C) find_last_of
D) find_first_not_of

Question 6

Which of the following is not an argument of the assign member function?

A) The start location.
B) The number of characters to copy.
C) The end location.
D) The string to copy.

Question 7

Which of the following is not overloaded for strings?

A) -=
B) >>
C) +=
D) getline()

Question 8

The arguments passed to replace do not include:

A) The subscript of the element where the replace operation ends.
B) The subscript of the element where the replace operation begins.
C) A replacement character string from which a substring is used to replace characters.
D) The element in the replacement character string where the replacement substring begins.

Question 9

Given the strings defined below, which statement will not return 0? string s1{"Mighty Mouse"};
String s2{"Mickey Mouse"};

A) s1.compare(0, 3, s2, 0, 3);
B) s1.compare(7, 5, s2, 7, 5);
C) s1.compare(8, 12, s2, 8, 12);
D) s1.compare(7, 11, s2, 7, 11);

Question 10

The function call string1.erase(5) will:

A) Return a copy of string1 minus the character that occupied position 5.
B) Erase all characters up to and including the character in position 5 from string1.
C) Erase all characters starting from and including the character in position 5 to the end of string1.
D) Return a copy of string1 minus every fifth character.

Question 11

Strings:

A) Can use the subscript operator to access individual characters.
B) Must be null-terminated.
C) Are pointers.
D) Have a first subscript of 1.

Question 12

If string s1 has the value "computer" and string s2 has the value "promise", which call to insert will produce the string "compromise"?

A) s1.insert(4, s2, 0, string::npos);
B) s1.insert(string::npos, s2, 0, 4);
C) s2.insert(0, s1, 0, 3);
D) s2.insert(3, s1, 0, 3);

Question 13

If string s1 is lexicographically greater than string s2, then the value returned by s2.compare(0, s2.size(), s1) must be?

A) 0
B) -1
C) A negative number.
D) A positive number.

Question 14

Which of the following is false?

A) If a string is converted to a C-style array using data, modifying the string could cause the pointer previously returned by data to become invalid.
B) Converting a string containing one or more null characters to a C-style string can cause logic errors.
C) c_str returns a character array of the same length as the string object it is called on.
D) copy implicitly converts a string to a non-null terminated character array.

Question 15

Which of the following returns a bool?

A) length
B) empty
C) capacity
D) resize

Question 16

If string s contains "antidisestablishmentarianism", then s.substr(7, 13) would be:

A) "establish"
B) "ishmenta"
C) "establi"
D) "establishment"

Question 17

Class string has member function __________ to interchange the data stored in two string objects

A) exchange
B) switch
C) swap
D) copyto

Question 18

The total number of elements that can be stored in a string without increasing its current amount of allocated memory is called its:

A) Size.
B) Length.
C) Capacity.
D) Maximum size.

Question 19

Which of the following cannot be used to concatenate strings?

A) +
B) +=
C) append
D) assign

Question 20

Which of the following would not return string::npos when used on the string s which contains "rack":

A) s.find_first_not_of("crackling");
B) s.find_first_not_of("packrat");
C) s.rfind("car");
D) s.find("ack");

Question 21

Which of the following provides bounds checking?

A) at
B) iterator
C) reverse_iterator
D) [ ]

Question 22

Which of the following does not apply to an istringstream object?

A) Data is stored in the object as characters.
B) Input from the object works identically to input from any file stream.
C) Data in a string can be appended to it.
D) It is used to inputs data from a string in memory to program variables.

Question 23

Which of the statements a), b) and c) is false?

A) C++11's header now contains functions for converting from numeric values to string objects and from string objects to numeric values.
B) The to_string function returns the string representation of its numeric argument and is overloaded for types int, unsigned int, long, unsigned long, long long, unsigned long long, float, double and long double.
C) Each C++11 function that converts a string to an integral type receives two parameters-a string containing the characters to convert and a pointer to a size_t variable where the function stores the index of the first character that was not converted (a null pointer, by default).
D) All of the above statements are true.

Question 24

Which of the following statements about C++11's functions for converting string objects to numeric values is false?

A) Each function attempts to convert its entire string argument to a numeric value.
B) If no conversion can be performed, an invalid_argument exception occurs.
C) If the result of the conversion is out of range for the function's return type, an out_of_range exception occurs.
D) None of the above.

Question 25

String iterators:

A) Must be dereferenced in order to access the character at each location.
B) Are not range checked.
C) Come in const and non-const forms.
D) All of the above.

Question 26

What is the code for a loop that iterates from the end of a string toward the beginning?

A) string::reverse_iterator i{s.begin()}; while (i != s.end())
{
Cout << *i;
++i;
}
B) string::reverse_iterator i{s.rbegin()}; while (i != s.rend())
{
Cout << *i;
++i;
}
C) string::reverse_iterator i{s.end()}; while (i != s.begin())
{
Cout << *i;
--i;
}
D) string::reverse_iterator i{s.rbegin()}; while (i != s.rend())
{
Cout << *i;
--i;
}

Question 27

All of the following are true of an ostringstream object except that:

A) It uses a string to store output data.
B) A stream insertion operation cannot be used to append additional data to it.
C) The string data it stores is dynamically allocated.
D) The data it stores can be accessed using the function str.

Question 28

The capabilities of inputting and outputting strings in memory are known as:

A) String i/o manipulation.
B) String stream processing.
C) Character handling.
D) Dynamic string operations.