Starting out with C++ Chapter 10 Pointers

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True/False: A pointer can be passed as an argument to a function.

True

True/False: A pointer with the value 0 (zero) is called the NULL pointer.

True

True/False: An array name is a pointer constant because the address it represents cannot be changed during run-time.

True

True/False: C++ does not perform array bounds checking.

True

A pointer variable is designed to store

a memory address.

Memory leaks occur in a program when

a programmer fails to use delete on a pointer whose memory was allocated by the new operator.

The statement int *ptr = new int; acquires memory to hold an integer and then

sets ptr to point to the allocated memory.

A ________ keeps track of dynamically-allocated memory and automatically deletes when it is no longer in use

smart pointer

The statement cin >> *p;

stores the keyboard input into the variable pointed to by p.

Any time you use the new operator, it is good practice to

use delete afterwards to free the memory allocated by new

Dynamic memory allocation occurs

when a variable is created at run-time.

Programs with memory leaks

will eventually crash if allowed to execute for long periods of time.

If arr is an array identifier and k is an integer, the expression arr[k] is equivalent to

*(arr + k)

The ________ and ________ operators can respectively be used to increment and decrement a pointer variable.

++, --

You may use the type pointer to a structure as the type of a function parameter. structure member. function return type. all of these none of these

All of these

True/False: Memory cannot be allocated after a program is already running.

False

True/False: You can use pass by value when passing a C++ unique pointer to a function.

False

True/False: If a unique pointer ( unique_ptr) p points to a block of memory, a second unique pointer can be made to point to the same block of memory by using the library function move(p).

True

True/False: It is legal to subtract a pointer variable from another pointer variable.

True

True/False: The expression *s->p; is only meaningful if s is a pointer to a structure and p is a pointer that is a member of that structure.

True

True/False: The expression s->m has the same meaning as (*s).m.

True

True/False: The expression s->m is meaningful only when s is a pointer to a structure and m is a member of the structure.

True

True/False: The statement Rectangle * boxPtr; defines a variable boxPtr to be a pointer pointing to a type Rectangle.

True

True/False: You can use pass by reference when passing a C++ unique pointer to a function

True

Every byte in the computer's memory is assigned a unique

address.

The term pointer can be used interchangeably with

address.

Which of the following statements is not valid C++ code? int ptr = &num1; int ptr = int *num1; float num1 = &ptr2; all of these are valid. all of these are invalid.

all of these are invalid.

When the ________ is placed in front of a variable name, it returns the address of that variable.

ampersand ( & )

A statement that displays the address of the variable num1 is

cout << &num1;.

The statement double *num;

defines a pointer variable called num.

If Circle is a structure type, the statement Circle *pcirc;

defines a structure pointer called pcirc.

Which of the following statements correctly deletes a dynamically-allocated array pointed to by p? delete p; p delete[ ]; delete [ ] p; delete array p; none of these

delete [ ] p;

The code segment int *ptr; has the same meaning as

int* ptr;.

A function may return a pointer, but the programmer must ensure that the pointer

is pointing to an object that is still valid after the return of the function

A function may return a pointer, but the programmer must ensure that the pointer

is pointing to an object that is still valid after the return of the function.

A C++ smart pointer

is used to ensure that memory that is no longer in use is automatically deleted.

The delete operator should only be used on pointers that

point to storage allocated by the new operator.

The statement int *ptr; means

ptr is a pointer variable that will store the address of an integer variable.

A unique pointer is a pointer

that points to a block of memory, and no other pointer is allowed to point to the same block.

A pointer may be initialized with

the address of an existing object of the appropriate type.

If a variable occupies more than one byte of memory, its address is

the address of the first byte of storage allocated to it.

When the less than ( < ) operator is used between two pointer variables, the expression is testing whether

the address of the first variable comes before the address of the second variable in the computer's memory

The set of operations supported by the unique_ptr class include

the dereferencing operators * and ->.

The statement cout << &num1; will output

the memory address of the variable called num1.

Suppose that a function dynamically allocates a block of memory with a local pointer variable p pointing to the allocated block. Suppose further that there are no other pointers referencing that block of memory, and the function returns without doing a delete on p. Then

the program will suffer from memory leaks.

To dereference a structure pointer and simultaneously access a member of the structure, the appropriate operator to use is

the structure pointer operator, ->.

The statement cout << *ptr; will output

the value stored in the variable whose address is contained in ptr.

A dangling pointer is a pointer

to a block of memory that has been deleted.

A reason for passing a pointer to a function is

to avoid the overhead of copying large data structures and to allow the called function to modify a variable accessible to the calling function are both true.

The statement shared_ptr<int> p(new int); involves

two allocations of two different dynamic blocks of memory.


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