calloc function - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to allocate memory for 10 integers using calloc.

C

int *arr = (int *)[1](10, sizeof(int));

Drag options to blanks, or click blank then click option'

Acalloc

Brealloc

Cfree

Dmalloc

Attempts:

3 left

💡 Hint

Common Mistakes

Using malloc instead of calloc when zero-initialization is needed.

Forgetting to cast the return value of calloc.

The calloc function allocates memory for an array of elements and initializes all bytes to zero.

2fill in blank

medium

Complete the code to check if calloc failed to allocate memory.

C

if (ptr == [1]) {
    printf("Allocation failed\n");
}

Drag options to blanks, or click blank then click option'

A1

BNULL

C0

D-1

Attempts:

3 left

💡 Hint

Common Mistakes

Checking if pointer equals 0 instead of NULL.

Not checking the pointer at all.

When calloc fails, it returns NULL. Checking for NULL ensures the program handles allocation failure.

3fill in blank

hard

Fix the error in the calloc usage to allocate memory for 5 doubles.

C

double *data = (double *)calloc([1], sizeof(double));

Drag options to blanks, or click blank then click option'

A5

Bsizeof(double)

Csizeof(int)

D10

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping the number of elements and size arguments.

Using sizeof(int) instead of sizeof(double).

The first argument to calloc is the number of elements, here 5. The second argument is the size of each element, which should be sizeof(double), but the blank is for the number of elements.

4fill in blank

hard

Fill both blanks to allocate memory for 8 characters and check if allocation succeeded.

C

char *buffer = (char *)[1]([2], sizeof(char));
if (buffer == NULL) {
    printf("Memory allocation failed\n");
}

Drag options to blanks, or click blank then click option'

Acalloc

Bmalloc

C8

D10

Attempts:

3 left

💡 Hint

Common Mistakes

Using malloc instead of calloc when zero-initialization is needed.

Not checking for NULL after allocation.

Use calloc to allocate and zero-initialize 8 characters. Then check if the pointer is NULL to detect failure.

5fill in blank

hard

Fill all three blanks to allocate memory for 12 floats, check allocation, and free the memory.

C

float *arr = (float *)[1]([2], sizeof(float));
if (arr == [3]) {
    printf("Allocation failed\n");
} else {
    free(arr);
}

Drag options to blanks, or click blank then click option'

Amalloc

B12

CNULL

Dcalloc

Attempts:

3 left

💡 Hint

Common Mistakes

Not freeing allocated memory.

Checking pointer against 0 instead of NULL.

Use calloc to allocate 12 floats. Check if the pointer is NULL to detect failure. If allocation succeeds, free the memory.