Question 1

Of the following expressions, ____ is the most commonly used. This is because such an expression allows each element in an array to be accessed as the address is "marched along" from the starting address of the array to the address of the last array element.
A)*ptNum--
B)*--ptNum
C)*ptNum++
D)*++ptNum

Accepted Answer

C) *ptNum++ is the most commonly used expression for accessing each element in an array sequentially. This is because it accesses the current value pointed to by ptNum and then increments the pointer to point to the next element in the array, effectively "marching along" the array.

Question 2

int *ptNum = &miles; is ____.
A)always valid
B)never valid
C)only valid if miles is declared as an integer variable before ptNum is declared
D)only valid if miles is declared as an array of integers before ptNum is declared

Accepted Answer

This statement is only valid if "miles" is declared as an integer variable before "ptNum" is declared, as "ptNum" is a pointer to an integer and thus can only store the address of an integer variable.

Question 3

Consider the following declarations of a function that receives an array of integers and finds the element with the maximum value:
(i) findMax(int *vals, int numEls)
(ii) findMax(int vals[], int numEls)
The address in vals may be modified ____.
A)only if the function is declared as in (i)
B)only if the function is declared as in (ii)
C)if either (i) or (ii) is used
D)in neither case because an array variable cannot be modified (it is a pointer constant)

Accepted Answer

The address in vals may be modified if either (i) or (ii) is used because the function is declared to receive a pointer to an integer, and the pointer may be modified to point to a different location in memory.

Question 4

If nums is a two-dimensional integer array, ____ refers to element nums[0][0].
A)*nums
B)*(*nums)
C)*(&nums)
D)&(*nums)

Accepted Answer

B) *(*nums) correctly dereferences the pointer to the first element of the first array, effectively accessing nums[0][0].

Question 5

If nums is a two-dimensional integer array, ____ refers to element nums[1][0].
A)*nums[1]
B)*nums[0]
C)*nums + 1
D)*nums++

Accepted Answer

The expression *nums[1] refers to the first element of the second row in a two-dimensional array, which is nums[1][0].

Question 6

A suitable equivalent to the function header calc(int pt[2][3]) is ____.
A)calc(int *(*pt))
B)calc(int (*pt)[])
C)calc(int (*pt)[2])
D)calc(int (*pt)[3])

Accepted Answer

The function header calc(int pt[2][3]) indicates a 2D array with 3 columns. The equivalent pointer notation is calc(int (*pt)[3]), which points to an array of 3 integers.

Question 7

The header line ____ declares calc to be a pointer to a function that returns an integer.
A)int *calc()
B)int (*calc)()
C)int &calc()
D)int calc(*)

Accepted Answer

Option B, "int (*calc)()" correctly declares calc as a pointer to a function that returns an integer. The parentheses around *calc are necessary to indicate that calc is a pointer to a function, rather than a function returning a pointer to an int.

Question 8

You can replace lines 5 and 6 in the following function with ____.
1 /* copy string2 to string1 */
2 void strcopy(char string1[], char string2[])
3 {
4 int i = 0;
5 while (string1[i] = string2[i])
6 i++;
7 }
A) while (*string1 = *string2) ;
B) while (*string1 = string2) ;
C) while (*string1++ = *string2++) ;
D) while (*++string1 = *++string2) ;

Accepted Answer

Option C is correct because it uses pointer arithmetic to copy each character from `string2` to `string1` and then increments both pointers. This effectively replaces the functionality of lines 5 and 6 in the original code, which copies characters from `string2` to `string1` one by one in a loop until it reaches the null terminator (which is represented by the condition becoming false when the copied character is '\0').

Question 9

After creating two variables as follows:
Char message1[81] = "this is a string";
Char *message2 = "this is a string";
The statement ____ is not valid in C.
A) message1 = "A new message";
B) message2 = "A new message";
C) message2 = message1;
D) message2[0] = 'T';

Accepted Answer

Option A is not valid because `message1` is an array name, which in C, is a constant pointer. You cannot change the base address of an array after its declaration.

Quiz 11: Arrays, Addresses, and Pointers

Of the following expressions, ____ is the most commonly used. This is because such an expression allows each element in an array to be accessed as the address is "marched along" from the starting address of the array to the address of the last array element.

int *ptNum = &miles; is ____.

Consider the following declarations of a function that receives an array of integers and finds the element with the maximum value: (i) findMax(int *vals, int numEls) (ii) findMax(int vals[], int numEls) The address in vals may be modified ____.

If nums is a two-dimensional integer array, ____ refers to element nums[0][0].

If nums is a two-dimensional integer array, ____ refers to element nums[1][0].

A suitable equivalent to the function header calc(int pt[2][3]) is ____.

The header line ____ declares calc to be a pointer to a function that returns an integer.

You can replace lines 5 and 6 in the following function with ____. 1 /* copy string2 to string1 */ 2 void strcopy(char string1[], char string2[]) 3 { 4 int i = 0; 5 while (string1[i] = string2[i]) 6 i++; 7 }

After creating two variables as follows: Char message1[81] = "this is a string"; Char *message2 = "this is a string"; The statement ____ is not valid in C.