Question 1

When an array is passed to a function, the array address is the only item actually passed.

Accepted Answer

When an array is passed to a function, what is actually passed is the address of the first element of the array, not the entire array itself. This means the function receives a reference to the array, allowing it to access and modify the array elements.

Question 2

If nums is a two-dimensional integer array, *(*(nums + 2) + 1) refers to element nums[1][2].

Accepted Answer

*(*(nums + 2) + 1) refers to the element at nums[2][1], as the first indexing moves to the third row (due to 0-based indexing, +2 moves us two rows down from the first row), and the second indexing moves to the second element of that row.

Question 3

The following code is valid in C:
char *message;
strcpy(message,"abcdef");

Accepted Answer

The pointer 'message' is not initialized and does not point to allocated memory, so attempting to copy a string into it with strcpy() will result in undefined behavior.

Question 4

Instead of initially creating a string as an array it is possible to create a string using a pointer.

Accepted Answer

In C programming, a string can be created using a pointer by dynamically allocating memory for the string using functions like `malloc` or by pointing the pointer to a string literal. This approach treats the string as an array of characters in memory, which the pointer references.

Question 5

The declaration char *seasons[4]; creates an array of four elements, where each element is a pointer to a character.

Accepted Answer

The declaration `char *seasons[4];` indeed creates an array of four elements, where each element is a pointer to a character, typically used to point to the first character of a string.

Question 6

&grade[3] is equivalent to ____; assume that grade is an array of integers, and each integer requires 4 bytes of storage..
A)&grade[0] + 3
B)&grade[0] + 4
C)&grade[0] + (3 * 4)
D)&grade[0] + (3 / 4)

Accepted Answer

In C, the expression &grade[3] gives the address of the 4th element in the array. Since each integer is 4 bytes, the address is calculated as the base address &grade[0] plus 3 times the size of an integer (3 * 4 bytes).

Question 7

The address operator in C is ____.
A)&
B)*
C)->
D)")"

Accepted Answer

The address operator in C is "&", which is used to determine the address of a variable.

Question 8

The indirection operator in C is ____.
A)&
B)*
C)->
D)")"

Accepted Answer

The indirection operator in C is "*", which is used to access the value at a pointer's address.

Question 9

If we store the address of grade[0] in a pointer named gPtr (using the assignment statement gPtr = &grade[0];), then, the expression ____ references grade[0].
A)gPtr(0)
B)gPtr
C)&gPtr
D)gPtr.

Accepted Answer

The answer of If we store the address of grade[0]...

Question 10

The ____ in the expression *(gPtr + 1) is an offset.
A)*
B)gPtr
C)+
D)1

Accepted Answer

The "1" in the expression *(gPtr + 1) represents an offset from the address pointed to by gPtr, indicating the next memory location based on the type of gPtr.

Question 11

If gPtr is a pointer that points to the first element of an integer array (and each integer requires four bytes of storage), ____ references the variable that is three integers beyond the variable pointed to by gPtr.
A)*gPtr + 3
B)*(gPtr + 3)
C)*(gPtr + 3 * 4)
D)*(gPtr + 3 / 4)

Accepted Answer

B is correct because adding 3 to the pointer moves it three integers (or 12 bytes, assuming each integer is 4 bytes) forward in memory. Dereferencing the new pointer with * gives the value of the variable at that new location.

Question 12

When working with pointers, the ____ tells the number of variables that are to be skipped over.
A)indirection operator
B)address operator
C)offset
D)address

Accepted Answer

The offset tells the number of variables that are to be skipped over when working with pointers. It is used to calculate the address of the data in memory by skipping the specified number of variables from a particular point.

Question 13

The expression ____ adds 3 to "the variable pointed to by gPtr."
A)*(gPtr + 3)
B)*gPtr + 3
C)gPtr + 3
D)&gPtr + 3

Accepted Answer

The correct expression is "*gPtr + 3" which dereferences the pointer gPtr to get the value it points to and then adds 3 to that value.

Question 14

When an array is created, the compiler automatically creates an internal ____ for it and stores the base address of the array in it.
A)pointer constant
B)pointer
C)symbolic constant
D)location

Accepted Answer

When an array is created, the compiler automatically creates an internal pointer constant for it, which stores the base address of the array. This allows the array elements to be accessed efficiently.

Question 15

Assuming grade is an array of ten integers, the statement ____ is invalid.
A)grade = &grade[2];
B)*grade = *(grade + 2);
C)*grade = *grade + 2;
D)*grade = *(&grade[2]) + 2;

Accepted Answer

Option A is invalid because it attempts to assign the address of an integer (the third element of the array) to an array variable, which is not allowed in C. Arrays cannot be assigned new addresses after their declaration.

Question 16

If numPtr is declared as a pointer variable, the expression ____ can also be written as numPtr[i].
A)*numPtr + i
B)(numPtr + i)
C)*numPtr
D)*(numPtr + i)

Accepted Answer

The expression `*(numPtr + i)` correctly dereferences the pointer after it has been incremented by `i` positions, which is equivalent to accessing the element at index `i` using array notation `numPtr[i]`.

Question 17

Pointers ____ be initialized when they are declared.
A)must
B)must not
C)can
D)cannot

Accepted Answer

Pointers can be initialized when they are declared, but it is not mandatory. They can also be assigned a value after declaration.

Question 18

In performing ____ on pointers, we must be careful to produce addresses that point to something meaningful.
A)comparisons
B)arithmetic
C)subscript operations
D)duplication

Accepted Answer

Arithmetic on pointers must be done carefully to ensure that the resulting address is meaningful and corresponds to a valid memory location within the intended data structure or array. Incorrect pointer arithmetic can lead to undefined behavior or access violations.

Question 19

Consider the declarations
Int nums[100];
Int *nPtr;
The statement ____ produces the same result as nPtr = nums;.
A)nPtr = &nums[0];
B)nPtr = nums[0];
C)nPtr = *nums[0];
D)nPtr = &nums;

Accepted Answer

Option A is correct because both statements set nPtr to point to the first element of the array nums. The name of the array, nums, when used without brackets, acts as a pointer to its first element, just like &nums[0].

Question 20

Adding ____ to a pointer causes the pointer to point to the next element of the original data type being pointed to.
A)1
B)1 * sizeof(data type being pointed to)
C)2
D)2 * sizeof(data type being pointed to)

Accepted Answer

Adding 1 to a pointer automatically adjusts the pointer to point to the next element of the type it is pointing to, taking into account the size of the data type.

Quiz 11: Arrays, Addresses, and Pointers

When an array is passed to a function, the array address is the only item actually passed.

If nums is a two-dimensional integer array, ((nums + 2) + 1) refers to element nums[1][2].

The following code is valid in C: char *message; strcpy(message,"abcdef");

Instead of initially creating a string as an array it is possible to create a string using a pointer.

The declaration char *seasons[4]; creates an array of four elements, where each element is a pointer to a character.

&grade[3] is equivalent to ____; assume that grade is an array of integers, and each integer requires 4 bytes of storage..

The address operator in C is ____.

The indirection operator in C is ____.

If we store the address of grade[0] in a pointer named gPtr (using the assignment statement gPtr = &grade[0];) , then, the expression ____ references grade[0].

The ____ in the expression *(gPtr + 1) is an offset.

If gPtr is a pointer that points to the first element of an integer array (and each integer requires four bytes of storage) , ____ references the variable that is three integers beyond the variable pointed to by gPtr.

When working with pointers, the ____ tells the number of variables that are to be skipped over.

The expression ____ adds 3 to "the variable pointed to by gPtr."

When an array is created, the compiler automatically creates an internal ____ for it and stores the base address of the array in it.

Assuming grade is an array of ten integers, the statement ____ is invalid.

If numPtr is declared as a pointer variable, the expression ____ can also be written as numPtr[i].

Pointers ____ be initialized when they are declared.

In performing ____ on pointers, we must be careful to produce addresses that point to something meaningful.

Consider the declarations Int nums[100]; Int *nPtr; The statement ____ produces the same result as nPtr = nums;.

Adding ____ to a pointer causes the pointer to point to the next element of the original data type being pointed to.